25807989 has 20 divisors (see below), whose sum is σ = 36916256. Its totient is φ = 16036032.

The previous prime is 25807987. The next prime is 25807993. The reversal of 25807989 is 98970852.

It is a happy number.

It is not a de Polignac number, because 25807989 - 2¹ = 25807987 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 (25807987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 250512 + ... + 250614.

Almost surely, 2^25807989 is an apocalyptic number.

It is an amenable number.

25807989 is a deficient number, since it is larger than the sum of its proper divisors (11108267).

25807989 is an frugal number, since it uses more digits than its factorization.

25807989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 48.

The square root of 25807989 is about 5080.1563952304. The cubic root of 25807989 is about 295.5185326257.

It can be divided in two parts, 25807 and 989, that added together give a triangular number (26796 = T₂₃₁).

The spelling of 25807989 in words is "twenty-five million, eight hundred seven thousand, nine hundred eighty-nine".