7971157 has 2 divisors, whose sum is σ = 7971158. Its totient is φ = 7971156.

The previous prime is 7971149. The next prime is 7971199. The reversal of 7971157 is 7511797.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7789681 + 181476 = 2791^2 + 426^2 .

It is a cyclic number.

It is not a de Polignac number, because 7971157 - 2³ = 7971149 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7971137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3985578 + 3985579.

It is an arithmetic number, because the mean of its divisors is an integer number (3985579).

Almost surely, 2^7971157 is an apocalyptic number.

It is an amenable number.

7971157 is a deficient number, since it is larger than the sum of its proper divisors (1).

7971157 is an equidigital number, since it uses as much as digits as its factorization.

7971157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15435, while the sum is 37.

The square root of 7971157 is about 2823.3237504757. The cubic root of 7971157 is about 199.7593522260.

It can be divided in two parts, 7971 and 157, that added together give a triangular number (8128 = T₁₂₇).

The spelling of 7971157 in words is "seven million, nine hundred seventy-one thousand, one hundred fifty-seven".