12561516 has 36 divisors (see below), whose sum is σ = 34640424. Its totient is φ = 3806400.

The previous prime is 12561511. The next prime is 12561529. The reversal of 12561516 is 61516521.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 12561516.

It is not an unprimeable number, because it can be changed into a prime (12561511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15465 + ... + 16256.

It is an arithmetic number, because the mean of its divisors is an integer number (962234).

Almost surely, 2^12561516 is an apocalyptic number.

It is an amenable number.

12561516 is an abundant number, since it is smaller than the sum of its proper divisors (22078908).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12561516 is a wasteful number, since it uses less digits than its factorization.

12561516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31742 (or 31737 counting only the distinct ones).

The product of its digits is 1800, while the sum is 27.

The square root of 12561516 is about 3544.2229049539. Note that the first 3 decimals coincide. The cubic root of 12561516 is about 232.4595281618.

It can be divided in two parts, 1256 and 1516, that added together give a palindrome (2772).

The spelling of 12561516 in words is "twelve million, five hundred sixty-one thousand, five hundred sixteen".