25666164 has 36 divisors (see below), whose sum is σ = 66464580. Its totient is φ = 8346240.

The previous prime is 25666153. The next prime is 25666181. The reversal of 25666164 is 46166652.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 7518564 + 18147600 = 2742^2 + 4260^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7219 + ... + 10170.

Almost surely, 2^25666164 is an apocalyptic number.

It is an amenable number.

25666164 is an abundant number, since it is smaller than the sum of its proper divisors (40798416).

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

25666164 is a wasteful number, since it uses less digits than its factorization.

25666164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17440 (or 17435 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 25666164 is about 5066.1784413895. The cubic root of 25666164 is about 294.9762079826.

The spelling of 25666164 in words is "twenty-five million, six hundred sixty-six thousand, one hundred sixty-four".