25555961 has 2 divisors, whose sum is σ = 25555962. Its totient is φ = 25555960.

The previous prime is 25555951. The next prime is 25555979. The reversal of 25555961 is 16955552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12996025 + 12559936 = 3605^2 + 3544^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25555961 is a prime.

It is a Chen prime.

It is equal to p_1598465 and since 25555961 and 1598465 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (25555951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12777980 + 12777981.

It is an arithmetic number, because the mean of its divisors is an integer number (12777981).

Almost surely, 2^25555961 is an apocalyptic number.

It is an amenable number.

25555961 is a deficient number, since it is larger than the sum of its proper divisors (1).

25555961 is an equidigital number, since it uses as much as digits as its factorization.

25555961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 67500, while the sum is 38.

The square root of 25555961 is about 5055.2903971978. The cubic root of 25555961 is about 294.5534217817.

The spelling of 25555961 in words is "twenty-five million, five hundred fifty-five thousand, nine hundred sixty-one".