81093988 has 24 divisors (see below), whose sum is σ = 146708352. Its totient is φ = 39198624.

The previous prime is 81093977. The next prime is 81093997. The reversal of 81093988 is 88939018.

It is a hoax number, since the sum of its digits (46) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13006 + ... + 18202.

It is an arithmetic number, because the mean of its divisors is an integer number (6112848).

Almost surely, 2^81093988 is an apocalyptic number.

It is an amenable number.

81093988 is a deficient number, since it is larger than the sum of its proper divisors (65614364).

81093988 is a wasteful number, since it uses less digits than its factorization.

81093988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5331 (or 5329 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 46.

The square root of 81093988 is about 9005.2200417314. The cubic root of 81093988 is about 432.8421572114.

The spelling of 81093988 in words is "eighty-one million, ninety-three thousand, nine hundred eighty-eight".