81630912 has 56 divisors (see below), whose sum is σ = 235622592. Its totient is φ = 24736000.

The previous prime is 81630881. The next prime is 81630919. The reversal of 81630912 is 21903618.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 81630912.

It is not an unprimeable number, because it can be changed into a prime (81630919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17214 + ... + 21437.

Almost surely, 2^81630912 is an apocalyptic number.

It is an amenable number.

81630912 is an abundant number, since it is smaller than the sum of its proper divisors (153991680).

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

81630912 is a wasteful number, since it uses less digits than its factorization.

81630912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38677 (or 38667 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 81630912 is about 9034.9826784560. The cubic root of 81630912 is about 433.7953405141.

The spelling of 81630912 in words is "eighty-one million, six hundred thirty thousand, nine hundred twelve".