25217664 has 64 divisors (see below), whose sum is σ = 70943040. Its totient is φ = 7909376.

The previous prime is 25217659. The next prime is 25217743. The reversal of 25217664 is 46671252.

It is a tau number, because it is divible by the number of its divisors (64).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4597 + ... + 8459.

It is an arithmetic number, because the mean of its divisors is an integer number (1108485).

Almost surely, 2^25217664 is an apocalyptic number.

25217664 is a gapful number since it is divisible by the number (24) 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 25217664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35471520).

25217664 is an abundant number, since it is smaller than the sum of its proper divisors (45725376).

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

25217664 is a wasteful number, since it uses less digits than its factorization.

25217664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3897 (or 3885 counting only the distinct ones).

The product of its digits is 20160, while the sum is 33.

The square root of 25217664 is about 5021.7192275156. The cubic root of 25217664 is about 293.2479273857.

The spelling of 25217664 in words is "twenty-five million, two hundred seventeen thousand, six hundred sixty-four".