25645121 has 4 divisors (see below), whose sum is σ = 26027952. Its totient is φ = 25262292.

The previous prime is 25645099. The next prime is 25645133. The reversal of 25645121 is 12154652.

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 25645121 - 2¹⁴ = 25628737 is a prime.

It is a super-2 number, since 2×25645121² = 1315344462209282, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (25645141) 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, 191315 + ... + 191448.

It is an arithmetic number, because the mean of its divisors is an integer number (6506988).

Almost surely, 2^25645121 is an apocalyptic number.

It is an amenable number.

25645121 is a deficient number, since it is larger than the sum of its proper divisors (382831).

25645121 is an equidigital number, since it uses as much as digits as its factorization.

25645121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382830.

The product of its digits is 2400, while the sum is 26.

The square root of 25645121 is about 5064.1012035701. The cubic root of 25645121 is about 294.8955715789.

Adding to 25645121 its reverse (12154652), we get a palindrome (37799773).

The spelling of 25645121 in words is "twenty-five million, six hundred forty-five thousand, one hundred twenty-one".