81302664 has 32 divisors (see below), whose sum is σ = 205128000. Its totient is φ = 26851392.

The previous prime is 81302659. The next prime is 81302671. The reversal of 81302664 is 46620318.

It is a super-2 number, since 2×81302664² = 13220246346993792, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12924 + ... + 18155.

It is an arithmetic number, because the mean of its divisors is an integer number (6410250).

Almost surely, 2^81302664 is an apocalyptic number.

It is an amenable number.

81302664 is an abundant number, since it is smaller than the sum of its proper divisors (123825336).

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

81302664 is a wasteful number, since it uses less digits than its factorization.

81302664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31197 (or 31193 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 81302664 is about 9016.7989885546. The cubic root of 81302664 is about 433.2131111593.

The spelling of 81302664 in words is "eighty-one million, three hundred two thousand, six hundred sixty-four".