81322659 has 12 divisors (see below), whose sum is σ = 128144952. Its totient is φ = 49286400.

The previous prime is 81322651. The next prime is 81322663. The reversal of 81322659 is 95622318.

It is not a de Polignac number, because 81322659 - 2³ = 81322651 is a prime.

It is a super-2 number, since 2×81322659² = 13226749733660562, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81322651) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 410622 + ... + 410819.

It is an arithmetic number, because the mean of its divisors is an integer number (10678746).

Almost surely, 2^81322659 is an apocalyptic number.

81322659 is a deficient number, since it is larger than the sum of its proper divisors (46822293).

81322659 is a wasteful number, since it uses less digits than its factorization.

81322659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 821458 (or 821455 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 81322659 is about 9017.9076841582. The cubic root of 81322659 is about 433.2486220341.

The spelling of 81322659 in words is "eighty-one million, three hundred twenty-two thousand, six hundred fifty-nine".