15932561 has 2 divisors, whose sum is σ = 15932562. Its totient is φ = 15932560.

The previous prime is 15932557. The next prime is 15932563. The reversal of 15932561 is 16523951.

15932561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12250000 + 3682561 = 3500^2 + 1919^2 .

It is a cyclic number.

It is not a de Polignac number, because 15932561 - 2² = 15932557 is a prime.

Together with 15932563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (15932563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7966280 + 7966281.

It is an arithmetic number, because the mean of its divisors is an integer number (7966281).

Almost surely, 2^15932561 is an apocalyptic number.

It is an amenable number.

15932561 is a deficient number, since it is larger than the sum of its proper divisors (1).

15932561 is an equidigital number, since it uses as much as digits as its factorization.

15932561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8100, while the sum is 32.

The square root of 15932561 is about 3991.5612233811. The cubic root of 15932561 is about 251.6296788372.

The spelling of 15932561 in words is "fifteen million, nine hundred thirty-two thousand, five hundred sixty-one".