81654657 has 16 divisors (see below), whose sum is σ = 127462272. Its totient is φ = 45521280.

The previous prime is 81654649. The next prime is 81654667. The reversal of 81654657 is 75645618.

It is not a de Polignac number, because 81654657 - 2³ = 81654649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81654607) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46558 + ... + 48279.

It is an arithmetic number, because the mean of its divisors is an integer number (7966392).

Almost surely, 2^81654657 is an apocalyptic number.

It is an amenable number.

81654657 is a deficient number, since it is larger than the sum of its proper divisors (45807615).

81654657 is a wasteful number, since it uses less digits than its factorization.

81654657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94888.

The product of its digits is 201600, while the sum is 42.

The square root of 81654657 is about 9036.2966418771. The cubic root of 81654657 is about 433.8373975876.

The spelling of 81654657 in words is "eighty-one million, six hundred fifty-four thousand, six hundred fifty-seven".