25123010921 has 2 divisors, whose sum is σ = 25123010922. Its totient is φ = 25123010920.

The previous prime is 25123010893. The next prime is 25123010933. The reversal of 25123010921 is 12901032152.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17172792025 + 7950218896 = 131045^2 + 89164^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25123010921 is a prime.

It is not a weakly prime, because it can be changed into another prime (25123010981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12561505460 + 12561505461.

It is an arithmetic number, because the mean of its divisors is an integer number (12561505461).

Almost surely, 2^25123010921 is an apocalyptic number.

It is an amenable number.

25123010921 is a deficient number, since it is larger than the sum of its proper divisors (1).

25123010921 is an equidigital number, since it uses as much as digits as its factorization.

25123010921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 26.

The spelling of 25123010921 in words is "twenty-five billion, one hundred twenty-three million, ten thousand, nine hundred twenty-one".