25497509 has 2 divisors, whose sum is σ = 25497510. Its totient is φ = 25497508.

The previous prime is 25497491. The next prime is 25497523. The reversal of 25497509 is 90579452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24453025 + 1044484 = 4945^2 + 1022^2 .

It is a cyclic number.

It is not a de Polignac number, because 25497509 - 2²⁰ = 24448933 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25497599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12748754 + 12748755.

It is an arithmetic number, because the mean of its divisors is an integer number (12748755).

Almost surely, 2^25497509 is an apocalyptic number.

It is an amenable number.

25497509 is a deficient number, since it is larger than the sum of its proper divisors (1).

25497509 is an equidigital number, since it uses as much as digits as its factorization.

25497509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 113400, while the sum is 41.

The square root of 25497509 is about 5049.5058174043. The cubic root of 25497509 is about 294.3286812625.

The spelling of 25497509 in words is "twenty-five million, four hundred ninety-seven thousand, five hundred nine".