79679821 has 16 divisors (see below), whose sum is σ = 87696000. Its totient is φ = 71951040.

The previous prime is 79679807. The next prime is 79679837. The reversal of 79679821 is 12897697.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 79679821 - 2⁷ = 79679693 is a prime.

It is a Duffinian number.

Its product of digits (381024) is a multiple of the sum of its prime divisors (756).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79679891) 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, 159430 + ... + 159928.

It is an arithmetic number, because the mean of its divisors is an integer number (5481000).

Almost surely, 2^79679821 is an apocalyptic number.

79679821 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

79679821 is a deficient number, since it is larger than the sum of its proper divisors (8016179).

79679821 is a wasteful number, since it uses less digits than its factorization.

79679821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 756.

The product of its digits is 381024, while the sum is 49.

The square root of 79679821 is about 8926.3554152857. The cubic root of 79679821 is about 430.3113321311.

The spelling of 79679821 in words is "seventy-nine million, six hundred seventy-nine thousand, eight hundred twenty-one".