25640611521529 has 2 divisors, whose sum is σ = 25640611521530. Its totient is φ = 25640611521528.

The previous prime is 25640611521523. The next prime is 25640611521601. The reversal of 25640611521529 is 92512511604652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22463476389225 + 3177135132304 = 4739565^2 + 1782452^2 .

It is a cyclic number.

It is not a de Polignac number, because 25640611521529 - 2³ = 25640611521521 is a prime.

It is not a weakly prime, because it can be changed into another prime (25640611521521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12820305760764 + 12820305760765.

It is an arithmetic number, because the mean of its divisors is an integer number (12820305760765).

Almost surely, 2^{25640611521529} is an apocalyptic number.

It is an amenable number.

25640611521529 is a deficient number, since it is larger than the sum of its proper divisors (1).

25640611521529 is an equidigital number, since it uses as much as digits as its factorization.

25640611521529 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296000, while the sum is 49.

The spelling of 25640611521529 in words is "twenty-five trillion, six hundred forty billion, six hundred eleven million, five hundred twenty-one thousand, five hundred twenty-nine".