25166721 has 8 divisors (see below), whose sum is σ = 33869664. Its totient is φ = 16620800.

The previous prime is 25166719. The next prime is 25166753. The reversal of 25166721 is 12766152.

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 25166721 - 2¹ = 25166719 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25146721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38880 + ... + 39521.

It is an arithmetic number, because the mean of its divisors is an integer number (4233708).

Almost surely, 2^25166721 is an apocalyptic number.

It is an amenable number.

25166721 is a deficient number, since it is larger than the sum of its proper divisors (8702943).

25166721 is a wasteful number, since it uses less digits than its factorization.

25166721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78511.

The product of its digits is 5040, while the sum is 30.

The square root of 25166721 is about 5016.6443964068. The cubic root of 25166721 is about 293.0503277983.

The spelling of 25166721 in words is "twenty-five million, one hundred sixty-six thousand, seven hundred twenty-one".