25406662121 has 2 divisors, whose sum is σ = 25406662122. Its totient is φ = 25406662120.

The previous prime is 25406662111. The next prime is 25406662133. The reversal of 25406662121 is 12126660452.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22000305625 + 3406356496 = 148325^2 + 58364^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25406662121 is a prime.

It is not a weakly prime, because it can be changed into another prime (25406662111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12703331060 + 12703331061.

It is an arithmetic number, because the mean of its divisors is an integer number (12703331061).

Almost surely, 2^25406662121 is an apocalyptic number.

It is an amenable number.

25406662121 is a deficient number, since it is larger than the sum of its proper divisors (1).

25406662121 is an equidigital number, since it uses as much as digits as its factorization.

25406662121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34560, while the sum is 35.

The spelling of 25406662121 in words is "twenty-five billion, four hundred six million, six hundred sixty-two thousand, one hundred twenty-one".