Search a number
-
+
31242240 = 211335113
BaseRepresentation
bin111011100101…
…1100000000000
32011210021022000
41313023200000
530444222430
63033344000
7526361151
oct167134000
964707260
1031242240
11166a9837
12a568000
13661b543
144213928
152b21e60
hex1dcb800

31242240 has 192 divisors, whose sum is σ = 112039200. Its totient is φ = 8257536.

The previous prime is 31242223. The next prime is 31242247. The reversal of 31242240 is 4224213.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31242247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 276424 + ... + 276536.

Almost surely, 231242240 is an apocalyptic number.

31242240 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 31242240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56019600).

31242240 is an abundant number, since it is smaller than the sum of its proper divisors (80796960).

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

31242240 is a wasteful number, since it uses less digits than its factorization.

31242240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 31242240 is about 5589.4758251557. The cubic root of 31242240 is about 314.9541883491.

Adding to 31242240 its reverse (4224213), we get a palindrome (35466453).

The spelling of 31242240 in words is "thirty-one million, two hundred forty-two thousand, two hundred forty".