2512165621 has 4 divisors (see below), whose sum is σ = 2871046432. Its totient is φ = 2153284812.

The previous prime is 2512165589. The next prime is 2512165673. The reversal of 2512165621 is 1265612152.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2512165621 - 2⁵ = 2512165589 is a prime.

It is a super-2 number, since 2×2512165621² = 12621952214668631282, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2512165121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 179440395 + ... + 179440408.

It is an arithmetic number, because the mean of its divisors is an integer number (717761608).

Almost surely, 2^2512165621 is an apocalyptic number.

It is an amenable number.

2512165621 is a deficient number, since it is larger than the sum of its proper divisors (358880811).

2512165621 is an equidigital number, since it uses as much as digits as its factorization.

2512165621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358880810.

The product of its digits is 7200, while the sum is 31.

The square root of 2512165621 is about 50121.5085666822. The cubic root of 2512165621 is about 1359.4067519609.

Adding to 2512165621 its reverse (1265612152), we get a palindrome (3777777773).

The spelling of 2512165621 in words is "two billion, five hundred twelve million, one hundred sixty-five thousand, six hundred twenty-one".