2156857097 has 2 divisors, whose sum is σ = 2156857098. Its totient is φ = 2156857096.

The previous prime is 2156857069. The next prime is 2156857151. The reversal of 2156857097 is 7907586512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1463904121 + 692952976 = 38261^2 + 26324^2 .

It is a cyclic number.

It is not a de Polignac number, because 2156857097 - 2²⁴ = 2140079881 is a prime.

It is not a weakly prime, because it can be changed into another prime (2156851097) 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, 1078428548 + 1078428549.

It is an arithmetic number, because the mean of its divisors is an integer number (1078428549).

Almost surely, 2^2156857097 is an apocalyptic number.

It is an amenable number.

2156857097 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156857097 is an equidigital number, since it uses as much as digits as its factorization.

2156857097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1058400, while the sum is 50.

The square root of 2156857097 is about 46441.9755932066. The cubic root of 2156857097 is about 1292.0335486453.

The spelling of 2156857097 in words is "two billion, one hundred fifty-six million, eight hundred fifty-seven thousand, ninety-seven".