25887979889 has 4 divisors (see below), whose sum is σ = 27013544256. Its totient is φ = 24762415524.

The previous prime is 25887979867. The next prime is 25887979907. The reversal of 25887979889 is 98897978852.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25887979889 - 2²⁰ = 25886931313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25887979489) 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, 562782149 + ... + 562782194.

It is an arithmetic number, because the mean of its divisors is an integer number (6753386064).

Almost surely, 2^25887979889 is an apocalyptic number.

It is an amenable number.

25887979889 is a deficient number, since it is larger than the sum of its proper divisors (1125564367).

25887979889 is a wasteful number, since it uses less digits than its factorization.

25887979889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1125564366.

The product of its digits is 1463132160, while the sum is 80.

The spelling of 25887979889 in words is "twenty-five billion, eight hundred eighty-seven million, nine hundred seventy-nine thousand, eight hundred eighty-nine".