25566121 has 4 divisors (see below), whose sum is σ = 29218432. Its totient is φ = 21913812.

The previous prime is 25566119. The next prime is 25566157. The reversal of 25566121 is 12166552.

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 25566121 - 2¹ = 25566119 is a prime.

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 25566121.

It is not an unprimeable number, because it can be changed into a prime (25567121) 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, 1826145 + ... + 1826158.

It is an arithmetic number, because the mean of its divisors is an integer number (7304608).

Almost surely, 2^25566121 is an apocalyptic number.

It is an amenable number.

25566121 is a deficient number, since it is larger than the sum of its proper divisors (3652311).

25566121 is an equidigital number, since it uses as much as digits as its factorization.

25566121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3652310.

The product of its digits is 3600, while the sum is 28.

The square root of 25566121 is about 5056.2951852122. The cubic root of 25566121 is about 294.5924507225.

The spelling of 25566121 in words is "twenty-five million, five hundred sixty-six thousand, one hundred twenty-one".