79521157 has 2 divisors, whose sum is σ = 79521158. Its totient is φ = 79521156.

The previous prime is 79521119. The next prime is 79521173. The reversal of 79521157 is 75112597.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58232161 + 21288996 = 7631^2 + 4614^2 .

It is a cyclic number.

It is not a de Polignac number, because 79521157 - 2¹⁵ = 79488389 is a prime.

It is a super-2 number, since 2×79521157² = 12647228821237298, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79521187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39760578 + 39760579.

It is an arithmetic number, because the mean of its divisors is an integer number (39760579).

Almost surely, 2^79521157 is an apocalyptic number.

79521157 is the 5149-th hex number.

It is an amenable number.

79521157 is a deficient number, since it is larger than the sum of its proper divisors (1).

79521157 is an equidigital number, since it uses as much as digits as its factorization.

79521157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22050, while the sum is 37.

The square root of 79521157 is about 8917.4635967858. The cubic root of 79521157 is about 430.0255203891.

It can be divided in two parts, 795 and 21157, that added together give a cube (21952 = 28³).

The spelling of 79521157 in words is "seventy-nine million, five hundred twenty-one thousand, one hundred fifty-seven".