25345121221 has 4 divisors (see below), whose sum is σ = 28965852832. Its totient is φ = 21724389612.

The previous prime is 25345121171. The next prime is 25345121233. The reversal of 25345121221 is 12212154352.

It is a happy number.

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 25345121221 - 2¹³ = 25345113029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25345121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25345121261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1810365795 + ... + 1810365808.

It is an arithmetic number, because the mean of its divisors is an integer number (7241463208).

Almost surely, 2^25345121221 is an apocalyptic number.

It is an amenable number.

25345121221 is a deficient number, since it is larger than the sum of its proper divisors (3620731611).

25345121221 is an equidigital number, since it uses as much as digits as its factorization.

25345121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3620731610.

The product of its digits is 4800, while the sum is 28.

Adding to 25345121221 its reverse (12212154352), we get a palindrome (37557275573).

The spelling of 25345121221 in words is "twenty-five billion, three hundred forty-five million, one hundred twenty-one thousand, two hundred twenty-one".