81296660 has 24 divisors (see below), whose sum is σ = 174695136. Its totient is φ = 31762080.

The previous prime is 81296653. The next prime is 81296701. The reversal of 81296660 is 6669218.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

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, 46406 + ... + 48125.

It is an arithmetic number, because the mean of its divisors is an integer number (7278964).

Almost surely, 2^81296660 is an apocalyptic number.

It is an amenable number.

81296660 is an abundant number, since it is smaller than the sum of its proper divisors (93398476).

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

81296660 is a wasteful number, since it uses less digits than its factorization.

81296660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94583 (or 94581 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 81296660 is about 9016.4660482919. The cubic root of 81296660 is about 433.2024469924.

The spelling of 81296660 in words is "eighty-one million, two hundred ninety-six thousand, six hundred sixty".