2565387397 has 6 divisors (see below), whose sum is σ = 2725169618. Its totient is φ = 2414481984.

The previous prime is 2565387337. The next prime is 2565387403. The reversal of 2565387397 is 7937835652.

It can be written as a sum of positive squares in 3 ways, for example, as 269156836 + 2296230561 = 16406^2 + 47919^2 .

It is not a de Polignac number, because 2565387397 - 2²³ = 2556998789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2565387337) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4438098 + ... + 4438675.

Almost surely, 2^2565387397 is an apocalyptic number.

It is an amenable number.

2565387397 is a deficient number, since it is larger than the sum of its proper divisors (159782221).

2565387397 is an equidigital number, since it uses as much as digits as its factorization.

2565387397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8876807 (or 8876790 counting only the distinct ones).

The product of its digits is 9525600, while the sum is 55.

The square root of 2565387397 is about 50649.6534736419. The cubic root of 2565387397 is about 1368.9397015638.

It can be divided in two parts, 25653 and 87397, that added together give a triangular number (113050 = T₄₇₅).

The spelling of 2565387397 in words is "two billion, five hundred sixty-five million, three hundred eighty-seven thousand, three hundred ninety-seven".