25247809 has 2 divisors, whose sum is σ = 25247810. Its totient is φ = 25247808.

The previous prime is 25247741. The next prime is 25247819. The reversal of 25247809 is 90874252.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19607184 + 5640625 = 4428^2 + 2375^2 .

It is a cyclic number.

It is not a de Polignac number, because 25247809 - 2⁹ = 25247297 is a prime.

It is not a weakly prime, because it can be changed into another prime (25247819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12623904 + 12623905.

It is an arithmetic number, because the mean of its divisors is an integer number (12623905).

Almost surely, 2^25247809 is an apocalyptic number.

It is an amenable number.

25247809 is a deficient number, since it is larger than the sum of its proper divisors (1).

25247809 is an equidigital number, since it uses as much as digits as its factorization.

25247809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 25247809 is about 5024.7197931825. The cubic root of 25247809 is about 293.3647296227.

The spelling of 25247809 in words is "twenty-five million, two hundred forty-seven thousand, eight hundred nine".