31923151640 has 16 divisors (see below), whose sum is σ = 71827091280. Its totient is φ = 12769260640.

The previous prime is 31923151619. The next prime is 31923151643. The reversal of 31923151640 is 4615132913.

It is a super-2 number, since 2×31923151640² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31923151640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31923151643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 399039356 + ... + 399039435.

It is an arithmetic number, because the mean of its divisors is an integer number (4489193205).

Almost surely, 2^31923151640 is an apocalyptic number.

It is an amenable number.

31923151640 is an abundant number, since it is smaller than the sum of its proper divisors (39903939640).

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

31923151640 is a wasteful number, since it uses less digits than its factorization.

31923151640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 798078802 (or 798078798 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 35.

The spelling of 31923151640 in words is "thirty-one billion, nine hundred twenty-three million, one hundred fifty-one thousand, six hundred forty".