25254721 has 4 divisors (see below), whose sum is σ = 25276500. Its totient is φ = 25232944.

The previous prime is 25254703. The next prime is 25254727. The reversal of 25254721 is 12745252.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24850225 + 404496 = 4985^2 + 636^2 .

It is a cyclic number.

It is not a de Polignac number, because 25254721 - 2⁵ = 25254689 is a prime.

It is an alternating number because its digits alternate between even and odd.

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 25254721.

It is not an unprimeable number, because it can be changed into a prime (25254727) 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, 9046 + ... + 11503.

It is an arithmetic number, because the mean of its divisors is an integer number (6319125).

Almost surely, 2^25254721 is an apocalyptic number.

It is an amenable number.

25254721 is a deficient number, since it is larger than the sum of its proper divisors (21779).

25254721 is a wasteful number, since it uses less digits than its factorization.

25254721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21778.

The product of its digits is 5600, while the sum is 28.

The square root of 25254721 is about 5025.4075456623. The cubic root of 25254721 is about 293.3914983085.

Adding to 25254721 its reverse (12745252), we get a palindrome (37999973).

The spelling of 25254721 in words is "twenty-five million, two hundred fifty-four thousand, seven hundred twenty-one".