25420121 has 4 divisors (see below), whose sum is σ = 25430244. Its totient is φ = 25410000.

The previous prime is 25420099. The next prime is 25420139. The reversal of 25420121 is 12102452.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 19044496 + 6375625 = 4364^2 + 2525^2 .

It is a cyclic number.

It is not a de Polignac number, because 25420121 - 2²² = 21225817 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 25420121.

It is not an unprimeable number, because it can be changed into a prime (25420621) 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, 1871 + ... + 7371.

It is an arithmetic number, because the mean of its divisors is an integer number (6357561).

Almost surely, 2^25420121 is an apocalyptic number.

It is an amenable number.

25420121 is a deficient number, since it is larger than the sum of its proper divisors (10123).

25420121 is an equidigital number, since it uses as much as digits as its factorization.

25420121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10122.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 25420121 is about 5041.8370659909. The cubic root of 25420121 is about 294.0306052024.

Adding to 25420121 its reverse (12102452), we get a palindrome (37522573).

The spelling of 25420121 in words is "twenty-five million, four hundred twenty thousand, one hundred twenty-one".