81631462392 has 96 divisors (see below), whose sum is σ = 230258836080. Its totient is φ = 27093553920.

The previous prime is 81631462379. The next prime is 81631462463. The reversal of 81631462392 is 29326413618.

81631462392 is a `hidden beast` number, since 8 + 1 + 6 + 3 + 14 + 623 + 9 + 2 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 362842 + ... + 543062.

Almost surely, 2^81631462392 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 81631462392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115129418040).

81631462392 is an abundant number, since it is smaller than the sum of its proper divisors (148627373688).

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

81631462392 is a wasteful number, since it uses less digits than its factorization.

81631462392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180475 (or 180459 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The spelling of 81631462392 in words is "eighty-one billion, six hundred thirty-one million, four hundred sixty-two thousand, three hundred ninety-two".