25611997 has 2 divisors, whose sum is σ = 25611998. Its totient is φ = 25611996.

The previous prime is 25611991. The next prime is 25612051. The reversal of 25611997 is 79911652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22174681 + 3437316 = 4709^2 + 1854^2 .

It is a cyclic number.

It is not a de Polignac number, because 25611997 - 2⁷ = 25611869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25611991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12805998 + 12805999.

It is an arithmetic number, because the mean of its divisors is an integer number (12805999).

Almost surely, 2^25611997 is an apocalyptic number.

It is an amenable number.

25611997 is a deficient number, since it is larger than the sum of its proper divisors (1).

25611997 is an equidigital number, since it uses as much as digits as its factorization.

25611997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34020, while the sum is 40.

The square root of 25611997 is about 5060.8296750632. The cubic root of 25611997 is about 294.7685515825.

The spelling of 25611997 in words is "twenty-five million, six hundred eleven thousand, nine hundred ninety-seven".