81302766 has 16 divisors (see below), whose sum is σ = 166387584. Its totient is φ = 26470584.

The previous prime is 81302737. The next prime is 81302777. The reversal of 81302766 is 66720318.

It is a super-2 number, since 2×81302766² = 13220279518501512, which contains 22 as substring.

It is a congruent number.

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, 157306 + ... + 157821.

It is an arithmetic number, because the mean of its divisors is an integer number (10399224).

Almost surely, 2^81302766 is an apocalyptic number.

81302766 is a gapful number since it is divisible by the number (86) formed by its first and last digit.

81302766 is an abundant number, since it is smaller than the sum of its proper divisors (85084818).

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

81302766 is a wasteful number, since it uses less digits than its factorization.

81302766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315175.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 81302766 is about 9016.8046446621. The cubic root of 81302766 is about 433.2132923249.

The spelling of 81302766 in words is "eighty-one million, three hundred two thousand, seven hundred sixty-six".