31861057638 has 16 divisors (see below), whose sum is σ = 64180549440. Its totient is φ = 10543946856.

The previous prime is 31861057619. The next prime is 31861057639. The reversal of 31861057638 is 83675016813.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31861057639) 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, 19100520 + ... + 19102187.

It is an arithmetic number, because the mean of its divisors is an integer number (4011284340).

Almost surely, 2^31861057638 is an apocalyptic number.

31861057638 is an abundant number, since it is smaller than the sum of its proper divisors (32319491802).

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

31861057638 is a wasteful number, since it uses less digits than its factorization.

31861057638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38202851.

The product of its (nonzero) digits is 725760, while the sum is 48.

The spelling of 31861057638 in words is "thirty-one billion, eight hundred sixty-one million, fifty-seven thousand, six hundred thirty-eight".