25139009 has 6 divisors (see below), whose sum is σ = 29243394. Its totient is φ = 21547680.

The previous prime is 25138999. The next prime is 25139017. The reversal of 25139009 is 90093152.

It can be written as a sum of positive squares in only one way, i.e., 17875984 + 7263025 = 4228^2 + 2695^2 .

It is not a de Polignac number, because 25139009 - 2⁸ = 25138753 is a prime.

It is a super-3 number, since 3×25139009³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25139509) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 256472 + ... + 256569.

It is an arithmetic number, because the mean of its divisors is an integer number (4873899).

Almost surely, 2^25139009 is an apocalyptic number.

It is an amenable number.

25139009 is a deficient number, since it is larger than the sum of its proper divisors (4104385).

25139009 is an equidigital number, since it uses as much as digits as its factorization.

25139009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 513055 (or 513048 counting only the distinct ones).

The product of its (nonzero) digits is 2430, while the sum is 29.

The square root of 25139009 is about 5013.8816300348. The cubic root of 25139009 is about 292.9427254705.

The spelling of 25139009 in words is "twenty-five million, one hundred thirty-nine thousand, nine".