25206563197 has 2 divisors, whose sum is σ = 25206563198. Its totient is φ = 25206563196.

The previous prime is 25206563177. The next prime is 25206563219. The reversal of 25206563197 is 79136560252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13498024761 + 11708538436 = 116181^2 + 108206^2 .

It is a cyclic number.

It is not a de Polignac number, because 25206563197 - 2¹⁵ = 25206530429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25206563177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12603281598 + 12603281599.

It is an arithmetic number, because the mean of its divisors is an integer number (12603281599).

Almost surely, 2^25206563197 is an apocalyptic number.

It is an amenable number.

25206563197 is a deficient number, since it is larger than the sum of its proper divisors (1).

25206563197 is an equidigital number, since it uses as much as digits as its factorization.

25206563197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 680400, while the sum is 46.

The spelling of 25206563197 in words is "twenty-five billion, two hundred six million, five hundred sixty-three thousand, one hundred ninety-seven".