31491789084 has 288 divisors, whose sum is σ = 96741765120. Its totient is φ = 8447846400.

The previous prime is 31491789079. The next prime is 31491789113. The reversal of 31491789084 is 48098719413.

31491789084 is a `hidden beast` number, since 3 + 1 + 491 + 78 + 9 + 0 + 84 = 666.

It is a super-2 number, since 2×31491789084² (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 31491789084.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 80955562 + ... + 80955950.

Almost surely, 2^31491789084 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 31491789084, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48370882560).

31491789084 is an abundant number, since it is smaller than the sum of its proper divisors (65249976036).

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

31491789084 is a wasteful number, since it uses less digits than its factorization.

31491789084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 721 (or 716 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 54.

The spelling of 31491789084 in words is "thirty-one billion, four hundred ninety-one million, seven hundred eighty-nine thousand, eighty-four".