81456408 has 64 divisors (see below), whose sum is σ = 246844800. Its totient is φ = 24683040.

The previous prime is 81456341. The next prime is 81456413. The reversal of 81456408 is 80465418.

81456408 is a `hidden beast` number, since 8 + 1 + 4 + 5 + 640 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14766 + ... + 19517.

It is an arithmetic number, because the mean of its divisors is an integer number (3856950).

Almost surely, 2^81456408 is an apocalyptic number.

81456408 is a gapful number since it is divisible by the number (88) formed by its first and last digit.

It is an amenable number.

81456408 is an abundant number, since it is smaller than the sum of its proper divisors (165388392).

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

81456408 is a wasteful number, since it uses less digits than its factorization.

81456408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34309 (or 34299 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 81456408 is about 9025.3203821249. The cubic root of 81456408 is about 433.4860090550.

The spelling of 81456408 in words is "eighty-one million, four hundred fifty-six thousand, four hundred eight".