31251687064 has 64 divisors (see below), whose sum is σ = 64669933440. Its totient is φ = 14068139520.

The previous prime is 31251687053. The next prime is 31251687157. The reversal of 31251687064 is 46078615213.

It is a self number, because there is not a number n which added to its sum of digits gives 31251687064.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1421274 + ... + 1443094.

It is an arithmetic number, because the mean of its divisors is an integer number (1010467710).

Almost surely, 2^31251687064 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31251687064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32334966720).

31251687064 is an abundant number, since it is smaller than the sum of its proper divisors (33418246376).

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

31251687064 is a wasteful number, since it uses less digits than its factorization.

31251687064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22180 (or 22176 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 43.

The spelling of 31251687064 in words is "thirty-one billion, two hundred fifty-one million, six hundred eighty-seven thousand, sixty-four".