25553921 has 4 divisors (see below), whose sum is σ = 25572144. Its totient is φ = 25535700.

The previous prime is 25553887. The next prime is 25553929. The reversal of 25553921 is 12935552.

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 25553921 - 2¹⁴ = 25537537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25553929) 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, 6815 + ... + 9876.

It is an arithmetic number, because the mean of its divisors is an integer number (6393036).

Almost surely, 2^25553921 is an apocalyptic number.

It is an amenable number.

25553921 is a deficient number, since it is larger than the sum of its proper divisors (18223).

25553921 is a wasteful number, since it uses less digits than its factorization.

25553921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18222.

The product of its digits is 13500, while the sum is 32.

The square root of 25553921 is about 5055.0886243468. The cubic root of 25553921 is about 294.5455840151.

The spelling of 25553921 in words is "twenty-five million, five hundred fifty-three thousand, nine hundred twenty-one".