12621565 has 16 divisors (see below), whose sum is σ = 17496000. Its totient is φ = 8638720.

The previous prime is 12621547. The next prime is 12621569. The reversal of 12621565 is 56512621.

It is not a de Polignac number, because 12621565 - 2⁵ = 12621533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12621569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5815 + ... + 7684.

It is an arithmetic number, because the mean of its divisors is an integer number (1093500).

Almost surely, 2^12621565 is an apocalyptic number.

It is an amenable number.

12621565 is a deficient number, since it is larger than the sum of its proper divisors (4874435).

12621565 is a wasteful number, since it uses less digits than its factorization.

12621565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13532.

The product of its digits is 3600, while the sum is 28.

The square root of 12621565 is about 3552.6841964914. The cubic root of 12621565 is about 232.8293555504.

The spelling of 12621565 in words is "twelve million, six hundred twenty-one thousand, five hundred sixty-five".