25159681 has 2 divisors, whose sum is σ = 25159682. Its totient is φ = 25159680.

The previous prime is 25159679. The next prime is 25159697. The reversal of 25159681 is 18695152.

25159681 = T₄₀₉₄ + T₄₀₉₅ + T₄₀₉₆.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23619600 + 1540081 = 4860^2 + 1241^2 .

It is a cyclic number.

It is not a de Polignac number, because 25159681 - 2¹ = 25159679 is a prime.

It is a super-2 number, since 2×25159681² = 1266019096043522, which contains 22 as substring.

Together with 25159679, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 25159681.

It is not a weakly prime, because it can be changed into another prime (25159481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12579840 + 12579841.

It is an arithmetic number, because the mean of its divisors is an integer number (12579841).

Almost surely, 2^25159681 is an apocalyptic number.

25159681 is the 4096-th centered triangular number.

It is an amenable number.

25159681 is a deficient number, since it is larger than the sum of its proper divisors (1).

25159681 is an equidigital number, since it uses as much as digits as its factorization.

25159681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21600, while the sum is 37.

The square root of 25159681 is about 5015.9426830856. The cubic root of 25159681 is about 293.0229998214.

The spelling of 25159681 in words is "twenty-five million, one hundred fifty-nine thousand, six hundred eighty-one".