25664878380 has 96 divisors (see below), whose sum is σ = 72955753920. Its totient is φ = 6740377600.

The previous prime is 25664878373. The next prime is 25664878397. The reversal of 25664878380 is 8387846652.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 25664878380.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1363030 + ... + 1381730.

It is an arithmetic number, because the mean of its divisors is an integer number (759955770).

Almost surely, 2^25664878380 is an apocalyptic number.

25664878380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25664878380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36477876960).

25664878380 is an abundant number, since it is smaller than the sum of its proper divisors (47290875540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25664878380 is a wasteful number, since it uses less digits than its factorization.

25664878380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19059 (or 19057 counting only the distinct ones).

The product of its (nonzero) digits is 15482880, while the sum is 57.

The spelling of 25664878380 in words is "twenty-five billion, six hundred sixty-four million, eight hundred seventy-eight thousand, three hundred eighty".