25206455221 has 2 divisors, whose sum is σ = 25206455222. Its totient is φ = 25206455220.

The previous prime is 25206455213. The next prime is 25206455257. The reversal of 25206455221 is 12255460252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21664896100 + 3541559121 = 147190^2 + 59511^2 .

It is a cyclic number.

It is not a de Polignac number, because 25206455221 - 2³ = 25206455213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25206452221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12603227610 + 12603227611.

It is an arithmetic number, because the mean of its divisors is an integer number (12603227611).

Almost surely, 2^25206455221 is an apocalyptic number.

It is an amenable number.

25206455221 is a deficient number, since it is larger than the sum of its proper divisors (1).

25206455221 is an equidigital number, since it uses as much as digits as its factorization.

25206455221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48000, while the sum is 34.

The spelling of 25206455221 in words is "twenty-five billion, two hundred six million, four hundred fifty-five thousand, two hundred twenty-one".