15564161 has 6 divisors (see below), whose sum is σ = 15997590. Its totient is φ = 15142176.

The previous prime is 15564149. The next prime is 15564179. The reversal of 15564161 is 16146551.

It can be written as a sum of positive squares in 3 ways, for example, as 9339136 + 6225025 = 3056^2 + 2495^2 .

It is not a de Polignac number, because 15564161 - 2¹⁸ = 15302017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15564181) 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, 4316 + ... + 7053.

It is an arithmetic number, because the mean of its divisors is an integer number (2666265).

Almost surely, 2^15564161 is an apocalyptic number.

It is an amenable number.

15564161 is a deficient number, since it is larger than the sum of its proper divisors (433429).

15564161 is an equidigital number, since it uses as much as digits as its factorization.

15564161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11443 (or 11406 counting only the distinct ones).

The product of its digits is 3600, while the sum is 29.

The square root of 15564161 is about 3945.1439770939. The cubic root of 15564161 is about 249.6751032847.

The spelling of 15564161 in words is "fifteen million, five hundred sixty-four thousand, one hundred sixty-one".