25995721 has 4 divisors (see below), whose sum is σ = 26151552. Its totient is φ = 25839892.

The previous prime is 25995691. The next prime is 25995731. The reversal of 25995721 is 12759952.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25995721 - 2¹¹ = 25993673 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25995731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77665 + ... + 77998.

It is an arithmetic number, because the mean of its divisors is an integer number (6537888).

Almost surely, 2^25995721 is an apocalyptic number.

It is an amenable number.

25995721 is a deficient number, since it is larger than the sum of its proper divisors (155831).

25995721 is a wasteful number, since it uses less digits than its factorization.

25995721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155830.

The product of its digits is 56700, while the sum is 40.

The square root of 25995721 is about 5098.5999058565. The cubic root of 25995721 is about 296.2333539995.

The spelling of 25995721 in words is "twenty-five million, nine hundred ninety-five thousand, seven hundred twenty-one".