79721880 has 64 divisors (see below), whose sum is σ = 273335040. Its totient is φ = 18221952.

The previous prime is 79721843. The next prime is 79721881. The reversal of 79721880 is 8812797.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79721881) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 46614 + ... + 48293.

It is an arithmetic number, because the mean of its divisors is an integer number (4270860).

Almost surely, 2^79721880 is an apocalyptic number.

79721880 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

79721880 is an abundant number, since it is smaller than the sum of its proper divisors (193613160).

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

79721880 is a wasteful number, since it uses less digits than its factorization.

79721880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94928 (or 94924 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 42.

The square root of 79721880 is about 8928.7109931949. The cubic root of 79721880 is about 430.3870321038.

It can be divided in two parts, 79721 and 880, that added together give a triangular number (80601 = T₄₀₁).

The spelling of 79721880 in words is "seventy-nine million, seven hundred twenty-one thousand, eight hundred eighty".