81583894 has 16 divisors (see below), whose sum is σ = 139997088. Its totient is φ = 34929792.

The previous prime is 81583871. The next prime is 81583903. The reversal of 81583894 is 49838518.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15912 + ... + 20404.

It is an arithmetic number, because the mean of its divisors is an integer number (8749818).

Almost surely, 2^81583894 is an apocalyptic number.

81583894 is a deficient number, since it is larger than the sum of its proper divisors (58413194).

81583894 is a wasteful number, since it uses less digits than its factorization.

81583894 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5799.

The product of its digits is 276480, while the sum is 46.

The square root of 81583894 is about 9032.3803064309. The cubic root of 81583894 is about 433.7120383025.

The spelling of 81583894 in words is "eighty-one million, five hundred eighty-three thousand, eight hundred ninety-four".