25045639 has 4 divisors (see below), whose sum is σ = 25176960. Its totient is φ = 24914320.

The previous prime is 25045621. The next prime is 25045649. The reversal of 25045639 is 93654052.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 25045639 - 2⁷ = 25045511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25045609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65374 + ... + 65755.

It is an arithmetic number, because the mean of its divisors is an integer number (6294240).

Almost surely, 2^25045639 is an apocalyptic number.

25045639 is a deficient number, since it is larger than the sum of its proper divisors (131321).

25045639 is a wasteful number, since it uses less digits than its factorization.

25045639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131320.

The product of its (nonzero) digits is 32400, while the sum is 34.

The square root of 25045639 is about 5004.5618189808. The cubic root of 25045639 is about 292.5795979830.

It can be divided in two parts, 2 and 5045639, that multiplied together give a triangular number (10091278 = T₄₄₉₂).

The spelling of 25045639 in words is "twenty-five million, forty-five thousand, six hundred thirty-nine".