2157015121 has 2 divisors, whose sum is σ = 2157015122. Its totient is φ = 2157015120.

The previous prime is 2157015089. The next prime is 2157015137. The reversal of 2157015121 is 1215107512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1084780096 + 1072235025 = 32936^2 + 32745^2 .

It is a cyclic number.

It is not a de Polignac number, because 2157015121 - 2⁵ = 2157015089 is a prime.

It is not a weakly prime, because it can be changed into another prime (2157015181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078507560 + 1078507561.

It is an arithmetic number, because the mean of its divisors is an integer number (1078507561).

Almost surely, 2^2157015121 is an apocalyptic number.

It is an amenable number.

2157015121 is a deficient number, since it is larger than the sum of its proper divisors (1).

2157015121 is an equidigital number, since it uses as much as digits as its factorization.

2157015121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 700, while the sum is 25.

The square root of 2157015121 is about 46443.6768677933. The cubic root of 2157015121 is about 1292.0651018597.

The spelling of 2157015121 in words is "two billion, one hundred fifty-seven million, fifteen thousand, one hundred twenty-one".