81306882 has 16 divisors (see below), whose sum is σ = 180682080. Its totient is φ = 27102276.

The previous prime is 81306881. The next prime is 81306899. The reversal of 81306882 is 28860318.

It is a super-2 number, since 2×81306882² = 13221618121123848, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81306881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 752788 + ... + 752895.

It is an arithmetic number, because the mean of its divisors is an integer number (11292630).

Almost surely, 2^81306882 is an apocalyptic number.

81306882 is an abundant number, since it is smaller than the sum of its proper divisors (99375198).

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

81306882 is a wasteful number, since it uses less digits than its factorization.

81306882 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1505694 (or 1505688 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 81306882 is about 9017.0328822734. The cubic root of 81306882 is about 433.2206027601.

Subtracting from 81306882 its reverse (28860318), we obtain a square (52446564 = 7242²).

The spelling of 81306882 in words is "eighty-one million, three hundred six thousand, eight hundred eighty-two".