15566461 has 2 divisors, whose sum is σ = 15566462. Its totient is φ = 15566460.

The previous prime is 15566459. The next prime is 15566489. The reversal of 15566461 is 16466551.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15163236 + 403225 = 3894^2 + 635^2 .

It is a cyclic number.

It is not a de Polignac number, because 15566461 - 2¹ = 15566459 is a prime.

Together with 15566459, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15563461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7783230 + 7783231.

It is an arithmetic number, because the mean of its divisors is an integer number (7783231).

Almost surely, 2^15566461 is an apocalyptic number.

It is an amenable number.

15566461 is a deficient number, since it is larger than the sum of its proper divisors (1).

15566461 is an equidigital number, since it uses as much as digits as its factorization.

15566461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21600, while the sum is 34.

The square root of 15566461 is about 3945.4354639254. The cubic root of 15566461 is about 249.6874012911.

The spelling of 15566461 in words is "fifteen million, five hundred sixty-six thousand, four hundred sixty-one".