25642499 has 2 divisors, whose sum is σ = 25642500. Its totient is φ = 25642498.

The previous prime is 25642489. The next prime is 25642501. The reversal of 25642499 is 99424652.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25642499 - 2⁴ = 25642483 is a prime.

It is a super-6 number, since 6×25642499⁶ (a number of 46 digits) contains 666666 as substring.

It is a Sophie Germain prime.

Together with 25642501, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25642439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12821249 + 12821250.

It is an arithmetic number, because the mean of its divisors is an integer number (12821250).

Almost surely, 2^25642499 is an apocalyptic number.

25642499 is a deficient number, since it is larger than the sum of its proper divisors (1).

25642499 is an equidigital number, since it uses as much as digits as its factorization.

25642499 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 41.

The square root of 25642499 is about 5063.8423158704. The cubic root of 25642499 is about 294.8855210311.

The spelling of 25642499 in words is "twenty-five million, six hundred forty-two thousand, four hundred ninety-nine".