2565991357 has 2 divisors, whose sum is σ = 2565991358. Its totient is φ = 2565991356.

The previous prime is 2565991319. The next prime is 2565991399. The reversal of 2565991357 is 7531995652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2074438116 + 491553241 = 45546^2 + 22171^2 .

It is a cyclic number.

It is not a de Polignac number, because 2565991357 - 2²⁷ = 2431773629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2565991957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1282995678 + 1282995679.

It is an arithmetic number, because the mean of its divisors is an integer number (1282995679).

Almost surely, 2^2565991357 is an apocalyptic number.

It is an amenable number.

2565991357 is a deficient number, since it is larger than the sum of its proper divisors (1).

2565991357 is an equidigital number, since it uses as much as digits as its factorization.

2565991357 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2551500, while the sum is 52.

The square root of 2565991357 is about 50655.6152563563. The cubic root of 2565991357 is about 1369.0471213307.

The spelling of 2565991357 in words is "two billion, five hundred sixty-five million, nine hundred ninety-one thousand, three hundred fifty-seven".