81979008 has 96 divisors (see below), whose sum is σ = 224954880. Its totient is φ = 26449920.

The previous prime is 81978997. The next prime is 81979043. The reversal of 81979008 is 80097918.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 645441 + ... + 645567.

It is an arithmetic number, because the mean of its divisors is an integer number (2343280).

Almost surely, 2^81979008 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 81979008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112477440).

81979008 is an abundant number, since it is smaller than the sum of its proper divisors (142975872).

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

81979008 is a wasteful number, since it uses less digits than its factorization.

81979008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226 (or 173 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 42.

The square root of 81979008 is about 9054.2259746485. The cubic root of 81979008 is about 434.4110725042.

It can be divided in two parts, 8197 and 9008, that added together give a triangular number (17205 = T₁₈₅).

The spelling of 81979008 in words is "eighty-one million, nine hundred seventy-nine thousand, eight".