25685813 has 2 divisors, whose sum is σ = 25685814. Its totient is φ = 25685812.

The previous prime is 25685797. The next prime is 25685833. The reversal of 25685813 is 31858652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25170289 + 515524 = 5017^2 + 718^2 .

It is a cyclic number.

It is not a de Polignac number, because 25685813 - 2⁴ = 25685797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25685833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12842906 + 12842907.

It is an arithmetic number, because the mean of its divisors is an integer number (12842907).

Almost surely, 2^25685813 is an apocalyptic number.

It is an amenable number.

25685813 is a deficient number, since it is larger than the sum of its proper divisors (1).

25685813 is an equidigital number, since it uses as much as digits as its factorization.

25685813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 57600, while the sum is 38.

The square root of 25685813 is about 5068.1173032991. The cubic root of 25685813 is about 295.0514628211.

The spelling of 25685813 in words is "twenty-five million, six hundred eighty-five thousand, eight hundred thirteen".