79331621 has 2 divisors, whose sum is σ = 79331622. Its totient is φ = 79331620.

The previous prime is 79331587. The next prime is 79331627. The reversal of 79331621 is 12613397.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47803396 + 31528225 = 6914^2 + 5615^2 .

It is a cyclic number.

It is not a de Polignac number, because 79331621 - 2⁶ = 79331557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79331627) 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 as a sum of consecutive naturals, namely, 39665810 + 39665811.

It is an arithmetic number, because the mean of its divisors is an integer number (39665811).

Almost surely, 2^79331621 is an apocalyptic number.

It is an amenable number.

79331621 is a deficient number, since it is larger than the sum of its proper divisors (1).

79331621 is an equidigital number, since it uses as much as digits as its factorization.

79331621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6804, while the sum is 32.

The square root of 79331621 is about 8906.8300197096. The cubic root of 79331621 is about 429.6835981424.

The spelling of 79331621 in words is "seventy-nine million, three hundred thirty-one thousand, six hundred twenty-one".