21115231125 has 32 divisors (see below), whose sum is σ = 35559119232. Its totient is φ = 11125760000.

The previous prime is 21115231087. The next prime is 21115231129. The reversal of 21115231125 is 52113251112.

It is not a de Polignac number, because 21115231125 - 2⁸ = 21115230869 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21115231095 and 21115231104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115231129) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 308076 + ... + 370325.

It is an arithmetic number, because the mean of its divisors is an integer number (1111222476).

Almost surely, 2^21115231125 is an apocalyptic number.

21115231125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21115231125 is a deficient number, since it is larger than the sum of its proper divisors (14443888107).

21115231125 is an equidigital number, since it uses as much as digits as its factorization.

21115231125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 678502 (or 678492 counting only the distinct ones).

The product of its digits is 600, while the sum is 24.

Adding to 21115231125 its reverse (52113251112), we get a palindrome (73228482237).

The spelling of 21115231125 in words is "twenty-one billion, one hundred fifteen million, two hundred thirty-one thousand, one hundred twenty-five".