25002211121 has 6 divisors (see below), whose sum is σ = 25027169622. Its totient is φ = 24977277440.

The previous prime is 25002211081. The next prime is 25002211127. The reversal of 25002211121 is 12111220052.

It can be written as a sum of positive squares in 3 ways, for example, as 13239724096 + 11762487025 = 115064^2 + 108455^2 .

It is a de Polignac number, because none of the positive numbers 2^k-25002211121 is a prime.

It is a super-2 number, since 2×25002211121² (a number of 22 digits) contains 22 as substring.

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 25002211121.

It is not an unprimeable number, because it can be changed into a prime (25002211127) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1089041 + ... + 1111761.

It is an arithmetic number, because the mean of its divisors is an integer number (4171194937).

Almost surely, 2^25002211121 is an apocalyptic number.

It is an amenable number.

25002211121 is a deficient number, since it is larger than the sum of its proper divisors (24958501).

25002211121 is an frugal number, since it uses more digits than its factorization.

25002211121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24819 (or 23770 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 17.

Adding to 25002211121 its reverse (12111220052), we get a palindrome (37113431173).

The spelling of 25002211121 in words is "twenty-five billion, two million, two hundred eleven thousand, one hundred twenty-one".