Search a number
-
+
31231312200 = 2332521129109499
BaseRepresentation
bin11101000101100010…
…000000000101001000
32222121120020001011200
4131011202000011020
51002430203442300
622203015224200
72153640526224
oct350542000510
988546201150
1031231312200
1112277297120
126077378060
132c395008ba
141723ba9784
15c2bc9c200
hex745880148

31231312200 has 576 divisors, whose sum is σ = 119691000000. Its totient is φ = 7228569600.

The previous prime is 31231312117. The next prime is 31231312201. The reversal of 31231312200 is 221313213.

31231312200 is a `hidden beast` number, since 312 + 3 + 131 + 220 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (31231312201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 62587551 + ... + 62588049.

It is an arithmetic number, because the mean of its divisors is an integer number (207796875).

Almost surely, 231231312200 is an apocalyptic number.

31231312200 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31231312200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59845500000).

31231312200 is an abundant number, since it is smaller than the sum of its proper divisors (88459687800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31231312200 is a wasteful number, since it uses less digits than its factorization.

31231312200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670 (or 658 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 31231312200 its reverse (221313213), we get a palindrome (31452625413).

The spelling of 31231312200 in words is "thirty-one billion, two hundred thirty-one million, three hundred twelve thousand, two hundred".