25605739517 has 2 divisors, whose sum is σ = 25605739518. Its totient is φ = 25605739516.

The previous prime is 25605739513. The next prime is 25605739531. The reversal of 25605739517 is 71593750652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20315941156 + 5289798361 = 142534^2 + 72731^2 .

It is a cyclic number.

It is not a de Polignac number, because 25605739517 - 2² = 25605739513 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25605739513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12802869758 + 12802869759.

It is an arithmetic number, because the mean of its divisors is an integer number (12802869759).

Almost surely, 2^25605739517 is an apocalyptic number.

It is an amenable number.

25605739517 is a deficient number, since it is larger than the sum of its proper divisors (1).

25605739517 is an equidigital number, since it uses as much as digits as its factorization.

25605739517 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1984500, while the sum is 50.

The spelling of 25605739517 in words is "twenty-five billion, six hundred five million, seven hundred thirty-nine thousand, five hundred seventeen".