25556513 has 2 divisors, whose sum is σ = 25556514. Its totient is φ = 25556512.

The previous prime is 25556507. The next prime is 25556527. The reversal of 25556513 is 31565552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13667809 + 11888704 = 3697^2 + 3448^2 .

It is a cyclic number.

It is not a de Polignac number, because 25556513 - 2¹⁰ = 25555489 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25556513.

It is not a weakly prime, because it can be changed into another prime (25556533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12778256 + 12778257.

It is an arithmetic number, because the mean of its divisors is an integer number (12778257).

Almost surely, 2^25556513 is an apocalyptic number.

It is an amenable number.

25556513 is a deficient number, since it is larger than the sum of its proper divisors (1).

25556513 is an equidigital number, since it uses as much as digits as its factorization.

25556513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22500, while the sum is 32.

The square root of 25556513 is about 5055.3449931731. The cubic root of 25556513 is about 294.5555425174. Note that the first 4 decimals are identical.

The spelling of 25556513 in words is "twenty-five million, five hundred fifty-six thousand, five hundred thirteen".