25797811997 has 2 divisors, whose sum is σ = 25797811998. Its totient is φ = 25797811996.

The previous prime is 25797811969. The next prime is 25797812071. The reversal of 25797811997 is 79911879752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24654966361 + 1142845636 = 157019^2 + 33806^2 .

It is a cyclic number.

It is not a de Polignac number, because 25797811997 - 2²⁴ = 25781034781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25797811927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12898905998 + 12898905999.

It is an arithmetic number, because the mean of its divisors is an integer number (12898905999).

Almost surely, 2^25797811997 is an apocalyptic number.

It is an amenable number.

25797811997 is a deficient number, since it is larger than the sum of its proper divisors (1).

25797811997 is an equidigital number, since it uses as much as digits as its factorization.

25797811997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20003760, while the sum is 65.

The spelling of 25797811997 in words is "twenty-five billion, seven hundred ninety-seven million, eight hundred eleven thousand, nine hundred ninety-seven".