25599040021 has 2 divisors, whose sum is σ = 25599040022. Its totient is φ = 25599040020.

The previous prime is 25599039953. The next prime is 25599040037. The reversal of 25599040021 is 12004099552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20499080625 + 5099959396 = 143175^2 + 71414^2 .

It is a cyclic number.

It is not a de Polignac number, because 25599040021 - 2⁹ = 25599039509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25599040091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12799520010 + 12799520011.

It is an arithmetic number, because the mean of its divisors is an integer number (12799520011).

Almost surely, 2^25599040021 is an apocalyptic number.

It is an amenable number.

25599040021 is a deficient number, since it is larger than the sum of its proper divisors (1).

25599040021 is an equidigital number, since it uses as much as digits as its factorization.

25599040021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32400, while the sum is 37.

The spelling of 25599040021 in words is "twenty-five billion, five hundred ninety-nine million, forty thousand, twenty-one".