Search a number
-
+
31312323220 = 2251798746459
BaseRepresentation
bin11101001010010111…
…000010001010010100
32222211012122211101211
4131022113002022110
51003111423320340
622215031431204
72155643233033
oct351227021224
988735584354
1031312323220
1112308a98982
12609a525504
132c50226209
14173085671a
15c33e505ea
hex74a5c2294

31312323220 has 24 divisors (see below), whose sum is σ = 66123237600. Its totient is φ = 12454956192.

The previous prime is 31312323199. The next prime is 31312323223. The reversal of 31312323220 is 2232321313.

It is a junction number, because it is equal to n+sod(n) for n = 31312323191 and 31312323200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31312323223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4369650 + ... + 4376809.

It is an arithmetic number, because the mean of its divisors is an integer number (2755134900).

Almost surely, 231312323220 is an apocalyptic number.

It is an amenable number.

31312323220 is an abundant number, since it is smaller than the sum of its proper divisors (34810914380).

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

31312323220 is a wasteful number, since it uses less digits than its factorization.

31312323220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8746647 (or 8746645 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 22.

Adding to 31312323220 its reverse (2232321313), we get a palindrome (33544644533).

The spelling of 31312323220 in words is "thirty-one billion, three hundred twelve million, three hundred twenty-three thousand, two hundred twenty".

Divisors: 1 2 4 5 10 20 179 358 716 895 1790 3580 8746459 17492918 34985836 43732295 87464590 174929180 1565616161 3131232322 6262464644 7828080805 15656161610 31312323220