81122657 has 32 divisors (see below), whose sum is σ = 110833920. Its totient is φ = 57415680.

The previous prime is 81122653. The next prime is 81122659. The reversal of 81122657 is 75622118.

It is not a de Polignac number, because 81122657 - 2² = 81122653 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81122653) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 36893 + ... + 39029.

It is an arithmetic number, because the mean of its divisors is an integer number (3463560).

Almost surely, 2^81122657 is an apocalyptic number.

It is an amenable number.

81122657 is a deficient number, since it is larger than the sum of its proper divisors (29711263).

81122657 is a wasteful number, since it uses less digits than its factorization.

81122657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2201.

The product of its digits is 6720, while the sum is 32.

The square root of 81122657 is about 9006.8117000413. The cubic root of 81122657 is about 432.8931584840.

The spelling of 81122657 in words is "eighty-one million, one hundred twenty-two thousand, six hundred fifty-seven".