25640689 has 8 divisors (see below), whose sum is σ = 26743808. Its totient is φ = 24554880.

The previous prime is 25640683. The next prime is 25640729. The reversal of 25640689 is 98604652.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25640689 - 2¹⁹ = 25116401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25640683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1257 + ... + 7270.

It is an arithmetic number, because the mean of its divisors is an integer number (3342976).

Almost surely, 2^25640689 is an apocalyptic number.

It is an amenable number.

25640689 is a deficient number, since it is larger than the sum of its proper divisors (1103119).

25640689 is an equidigital number, since it uses as much as digits as its factorization.

25640689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8655.

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 25640689 is about 5063.6635946714. The cubic root of 25640689 is about 294.8785826102.

The spelling of 25640689 in words is "twenty-five million, six hundred forty thousand, six hundred eighty-nine".