81083680 has 24 divisors (see below), whose sum is σ = 191560572. Its totient is φ = 32433408.

The previous prime is 81083657. The next prime is 81083699. The reversal of 81083680 is 8638018.

It can be written as a sum of positive squares in 2 ways, for example, as 81072016 + 11664 = 9004^2 + 108^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253227 + ... + 253546.

Almost surely, 2^81083680 is an apocalyptic number.

81083680 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81083680 is an abundant number, since it is smaller than the sum of its proper divisors (110476892).

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

81083680 is a wasteful number, since it uses less digits than its factorization.

81083680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506788 (or 506780 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 81083680 is about 9004.6476888327. The cubic root of 81083680 is about 432.8238166573.

The spelling of 81083680 in words is "eighty-one million, eighty-three thousand, six hundred eighty".