25661929 has 2 divisors, whose sum is σ = 25661930. Its totient is φ = 25661928.

The previous prime is 25661869. The next prime is 25661939. The reversal of 25661929 is 92916652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19669225 + 5992704 = 4435^2 + 2448^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25661929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25661891 and 25661900.

It is not a weakly prime, because it can be changed into another prime (25661939) 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, 12830964 + 12830965.

It is an arithmetic number, because the mean of its divisors is an integer number (12830965).

Almost surely, 2^25661929 is an apocalyptic number.

It is an amenable number.

25661929 is a deficient number, since it is larger than the sum of its proper divisors (1).

25661929 is an equidigital number, since it uses as much as digits as its factorization.

25661929 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58320, while the sum is 40.

The square root of 25661929 is about 5065.7604562395. The cubic root of 25661929 is about 294.9599830810.

The spelling of 25661929 in words is "twenty-five million, six hundred sixty-one thousand, nine hundred twenty-nine".