82566981 has 48 divisors (see below), whose sum is σ = 143024128. Its totient is φ = 44906400.

The previous prime is 82566961. The next prime is 82566983. The reversal of 82566981 is 18966528.

82566981 is a `hidden beast` number, since 8 + 2 + 566 + 9 + 81 = 666.

It is not a de Polignac number, because 82566981 - 2⁵ = 82566949 is a prime.

It is a super-2 number, since 2×82566981² = 13634612702908722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82566983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 130536 + ... + 131166.

Almost surely, 2^82566981 is an apocalyptic number.

It is an amenable number.

82566981 is a deficient number, since it is larger than the sum of its proper divisors (60457147).

82566981 is a wasteful number, since it uses less digits than its factorization.

82566981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742 (or 739 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 82566981 is about 9086.6374968962. The cubic root of 82566981 is about 435.4471660125.

The spelling of 82566981 in words is "eighty-two million, five hundred sixty-six thousand, nine hundred eighty-one".