81559832 has 16 divisors (see below), whose sum is σ = 158198400. Its totient is φ = 39373600.

The previous prime is 81559813. The next prime is 81559843. The reversal of 81559832 is 23895518.

It is a self number, because there is not a number n which added to its sum of digits gives 81559832.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 175544 + ... + 176007.

It is an arithmetic number, because the mean of its divisors is an integer number (9887400).

Almost surely, 2^81559832 is an apocalyptic number.

It is an amenable number.

81559832 is a deficient number, since it is larger than the sum of its proper divisors (76638568).

81559832 is a wasteful number, since it uses less digits than its factorization.

81559832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351586 (or 351582 counting only the distinct ones).

The product of its digits is 86400, while the sum is 41.

The square root of 81559832 is about 9031.0482226594. The cubic root of 81559832 is about 433.6693950605.

The spelling of 81559832 in words is "eighty-one million, five hundred fifty-nine thousand, eight hundred thirty-two".