2565371161 has 4 divisors (see below), whose sum is σ = 2565502132. Its totient is φ = 2565240192.

The previous prime is 2565371147. The next prime is 2565371167. The reversal of 2565371161 is 1611735652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2078904025 + 486467136 = 45595^2 + 22056^2 .

It is a cyclic number.

It is not a de Polignac number, because 2565371161 - 2¹⁵ = 2565338393 is a prime.

It is a super-2 number, since 2×2565371161² = 13162258387380975842, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2565371161.

It is not an unprimeable number, because it can be changed into a prime (2565371167) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29520 + ... + 77473.

It is an arithmetic number, because the mean of its divisors is an integer number (641375533).

Almost surely, 2^2565371161 is an apocalyptic number.

It is an amenable number.

2565371161 is a deficient number, since it is larger than the sum of its proper divisors (130971).

2565371161 is a wasteful number, since it uses less digits than its factorization.

2565371161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130970.

The product of its digits is 37800, while the sum is 37.

The square root of 2565371161 is about 50649.4931958850. The cubic root of 2565371161 is about 1368.9368136112.

The spelling of 2565371161 in words is "two billion, five hundred sixty-five million, three hundred seventy-one thousand, one hundred sixty-one".