31381618860 has 192 divisors, whose sum is σ = 103486602240. Its totient is φ = 7867653120.

The previous prime is 31381618841. The next prime is 31381618871. The reversal of 31381618860 is 6881618313.

31381618860 is a `hidden beast` number, since 31 + 381 + 6 + 188 + 60 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 16807647 + ... + 16809513.

It is an arithmetic number, because the mean of its divisors is an integer number (538992720).

Almost surely, 2^31381618860 is an apocalyptic number.

31381618860 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 31381618860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51743301120).

31381618860 is an abundant number, since it is smaller than the sum of its proper divisors (72104983380).

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

31381618860 is a wasteful number, since it uses less digits than its factorization.

31381618860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3733 (or 3725 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 31381618860 in words is "thirty-one billion, three hundred eighty-one million, six hundred eighteen thousand, eight hundred sixty".