25649161 has 2 divisors, whose sum is σ = 25649162. Its totient is φ = 25649160.

The previous prime is 25649159. The next prime is 25649171. The reversal of 25649161 is 16194652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25452025 + 197136 = 5045^2 + 444^2 .

It is a cyclic number.

It is not a de Polignac number, because 25649161 - 2¹ = 25649159 is a prime.

Together with 25649159, it forms a pair of twin primes.

It is the 5065-th Hogben number.

It is not a weakly prime, because it can be changed into another prime (25649101) by changing a digit.

It is a nontrivial repunit in base 5064.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12824580 + 12824581.

It is an arithmetic number, because the mean of its divisors is an integer number (12824581).

Almost surely, 2^25649161 is an apocalyptic number.

It is an amenable number.

25649161 is a deficient number, since it is larger than the sum of its proper divisors (1).

25649161 is an equidigital number, since it uses as much as digits as its factorization.

25649161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 34.

The square root of 25649161 is about 5064.5000740448. The cubic root of 25649161 is about 294.9110562079.

The spelling of 25649161 in words is "twenty-five million, six hundred forty-nine thousand, one hundred sixty-one".