25663681 has 8 divisors (see below), whose sum is σ = 26440704. Its totient is φ = 24891120.

The previous prime is 25663679. The next prime is 25663697. The reversal of 25663681 is 18636652.

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

It is a cyclic number.

It is not a de Polignac number, because 25663681 - 2¹ = 25663679 is a prime.

It is a super-2 number, since 2×25663681² = 1317249044939522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25663681.

It is not an unprimeable number, because it can be changed into a prime (25663601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13266 + ... + 15076.

It is an arithmetic number, because the mean of its divisors is an integer number (3305088).

Almost surely, 2^25663681 is an apocalyptic number.

It is an amenable number.

25663681 is a deficient number, since it is larger than the sum of its proper divisors (777023).

25663681 is a wasteful number, since it uses less digits than its factorization.

25663681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2231.

The product of its digits is 51840, while the sum is 37.

The square root of 25663681 is about 5065.9333789540. The cubic root of 25663681 is about 294.9666954645.

The spelling of 25663681 in words is "twenty-five million, six hundred sixty-three thousand, six hundred eighty-one".