81732232920 has 96 divisors (see below), whose sum is σ = 265508917200. Its totient is φ = 20118698496.

The previous prime is 81732232877. The next prime is 81732232921. The reversal of 81732232920 is 2923223718.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81732232921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1994815 + ... + 2035374.

Almost surely, 2^81732232920 is an apocalyptic number.

It is an amenable number.

81732232920 is an abundant number, since it is smaller than the sum of its proper divisors (183776684280).

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

81732232920 is a wasteful number, since it uses less digits than its factorization.

81732232920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4030229 (or 4030212 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 39.

The spelling of 81732232920 in words is "eighty-one billion, seven hundred thirty-two million, two hundred thirty-two thousand, nine hundred twenty".