25270721 has 24 divisors (see below), whose sum is σ = 32503680. Its totient is φ = 19485312.

The previous prime is 25270711. The next prime is 25270753. The reversal of 25270721 is 12707252.

It is not a de Polignac number, because 25270721 - 2¹⁰ = 25269697 is a prime.

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

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25270711) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18500 + ... + 19818.

It is an arithmetic number, because the mean of its divisors is an integer number (1354320).

Almost surely, 2^25270721 is an apocalyptic number.

It is an amenable number.

25270721 is a deficient number, since it is larger than the sum of its proper divisors (7232959).

25270721 is a wasteful number, since it uses less digits than its factorization.

25270721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1373 (or 1366 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 25270721 is about 5026.9992042967. Note that the first 3 decimals coincide. The cubic root of 25270721 is about 293.4534441255.

Adding to 25270721 its reverse (12707252), we get a palindrome (37977973).

The spelling of 25270721 in words is "twenty-five million, two hundred seventy thousand, seven hundred twenty-one".