81982658 has 16 divisors (see below), whose sum is σ = 125315640. Its totient is φ = 40214400.

The previous prime is 81982613. The next prime is 81982661. The reversal of 81982658 is 85628918.

It can be written as a sum of positive squares in 4 ways, for example, as 53392249 + 28590409 = 7307^2 + 5347^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68828 + ... + 70008.

Almost surely, 2^81982658 is an apocalyptic number.

81982658 is a deficient number, since it is larger than the sum of its proper divisors (43332982).

81982658 is a wasteful number, since it uses less digits than its factorization.

81982658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1813.

The product of its digits is 276480, while the sum is 47.

The square root of 81982658 is about 9054.4275357418. The cubic root of 81982658 is about 434.4175195891.

The spelling of 81982658 in words is "eighty-one million, nine hundred eighty-two thousand, six hundred fifty-eight".