25664421894 has 8 divisors (see below), whose sum is σ = 51328843800. Its totient is φ = 8554807296.

The previous prime is 25664421889. The next prime is 25664421911. The reversal of 25664421894 is 49812446652.

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

25664421894 is an admirable number.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2138701819 + ... + 2138701830.

It is an arithmetic number, because the mean of its divisors is an integer number (6416105475).

Almost surely, 2^25664421894 is an apocalyptic number.

25664421894 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

25664421894 is a wasteful number, since it uses less digits than its factorization.

25664421894 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4277403654.

The product of its digits is 3317760, while the sum is 51.

The spelling of 25664421894 in words is "twenty-five billion, six hundred sixty-four million, four hundred twenty-one thousand, eight hundred ninety-four".