81980576 has 24 divisors (see below), whose sum is σ = 163677024. Its totient is φ = 40411840.

The previous prime is 81980543. The next prime is 81980599. The reversal of 81980576 is 67508918.

It is a happy number.

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, 15770 + ... + 20313.

It is an arithmetic number, because the mean of its divisors is an integer number (6819876).

Almost surely, 2^81980576 is an apocalyptic number.

It is an amenable number.

81980576 is a deficient number, since it is larger than the sum of its proper divisors (81696448).

81980576 is a wasteful number, since it uses less digits than its factorization.

81980576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36164 (or 36156 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 44.

The square root of 81980576 is about 9054.3125636351. The cubic root of 81980576 is about 434.4138421247.

The spelling of 81980576 in words is "eighty-one million, nine hundred eighty thousand, five hundred seventy-six".