79159921 has 2 divisors, whose sum is σ = 79159922. Its totient is φ = 79159920.

The previous prime is 79159901. The next prime is 79159933. The reversal of 79159921 is 12995197.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44408896 + 34751025 = 6664^2 + 5895^2 .

It is an emirp because it is prime and its reverse (12995197) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79159921 - 2¹⁷ = 79028849 is a prime.

It is not a weakly prime, because it can be changed into another prime (79159901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39579960 + 39579961.

It is an arithmetic number, because the mean of its divisors is an integer number (39579961).

Almost surely, 2^79159921 is an apocalyptic number.

It is an amenable number.

79159921 is a deficient number, since it is larger than the sum of its proper divisors (1).

79159921 is an equidigital number, since it uses as much as digits as its factorization.

79159921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51030, while the sum is 43.

The square root of 79159921 is about 8897.1861282093. The cubic root of 79159921 is about 429.3733815154.

It can be divided in two parts, 79 and 159921, that added together give a 4-th power (160000 = 20⁴).

The spelling of 79159921 in words is "seventy-nine million, one hundred fifty-nine thousand, nine hundred twenty-one".