81597456 has 120 divisors (see below), whose sum is σ = 244817664. Its totient is φ = 26282880.

The previous prime is 81597449. The next prime is 81597463. The reversal of 81597456 is 65479518.

81597456 is a `hidden beast` number, since 8 + 1 + 597 + 4 + 56 = 666.

It is an interprime number because it is at equal distance from previous prime (81597449) and next prime (81597463).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 120190 + ... + 120866.

Almost surely, 2^81597456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81597456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122408832).

81597456 is an abundant number, since it is smaller than the sum of its proper divisors (163220208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81597456 is a wasteful number, since it uses less digits than its factorization.

81597456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 731 (or 713 counting only the distinct ones).

The product of its digits is 302400, while the sum is 45.

The square root of 81597456 is about 9033.1310186446. The cubic root of 81597456 is about 433.7360695031.

The spelling of 81597456 in words is "eighty-one million, five hundred ninety-seven thousand, four hundred fifty-six".