25489217979 has 12 divisors (see below), whose sum is σ = 38087337600. Its totient is φ = 16406852784.

The previous prime is 25489217959. The next prime is 25489217981. The reversal of 25489217979 is 97971298452.

25489217979 is a `hidden beast` number, since 2 + 548 + 9 + 2 + 17 + 9 + 79 = 666.

It is not a de Polignac number, because 25489217979 - 2⁷ = 25489217851 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25489217909) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 48829659 + ... + 48830180.

It is an arithmetic number, because the mean of its divisors is an integer number (3173944800).

Almost surely, 2^25489217979 is an apocalyptic number.

25489217979 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

25489217979 is a deficient number, since it is larger than the sum of its proper divisors (12598119621).

25489217979 is a wasteful number, since it uses less digits than its factorization.

25489217979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97659874 (or 97659871 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 63.

The spelling of 25489217979 in words is "twenty-five billion, four hundred eighty-nine million, two hundred seventeen thousand, nine hundred seventy-nine".