25670861 has 2 divisors, whose sum is σ = 25670862. Its totient is φ = 25670860.

The previous prime is 25670857. The next prime is 25670863. The reversal of 25670861 is 16807652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17724100 + 7946761 = 4210^2 + 2819^2 .

It is a cyclic number.

It is not a de Polignac number, because 25670861 - 2² = 25670857 is a prime.

It is a Sophie Germain prime.

Together with 25670863, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25670863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12835430 + 12835431.

It is an arithmetic number, because the mean of its divisors is an integer number (12835431).

Almost surely, 2^25670861 is an apocalyptic number.

It is an amenable number.

25670861 is a deficient number, since it is larger than the sum of its proper divisors (1).

25670861 is an equidigital number, since it uses as much as digits as its factorization.

25670861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 25670861 is about 5066.6419845890. The cubic root of 25670861 is about 294.9942007861.

It can be divided in two parts, 256 and 70861, that added together give a palindrome (71117).

The spelling of 25670861 in words is "twenty-five million, six hundred seventy thousand, eight hundred sixty-one".