79443679721 has 16 divisors (see below), whose sum is σ = 93314365440. Its totient is φ = 66229122960.

The previous prime is 79443679717. The next prime is 79443679741. The reversal of 79443679721 is 12797634497.

It is a happy number.

It is not a de Polignac number, because 79443679721 - 2² = 79443679717 is a prime.

It is a super-2 number, since 2×79443679721² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79443679741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1035035 + ... + 1109136.

It is an arithmetic number, because the mean of its divisors is an integer number (5832147840).

Almost surely, 2^79443679721 is an apocalyptic number.

It is an amenable number.

79443679721 is a deficient number, since it is larger than the sum of its proper divisors (13870685719).

79443679721 is a wasteful number, since it uses less digits than its factorization.

79443679721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2144324.

The product of its digits is 16003008, while the sum is 59.

The spelling of 79443679721 in words is "seventy-nine billion, four hundred forty-three million, six hundred seventy-nine thousand, seven hundred twenty-one".