21311110163125 has 40 divisors (see below), whose sum is σ = 26702758200888. Its totient is φ = 17002560000000.

The previous prime is 21311110163111. The next prime is 21311110163131. The reversal of 21311110163125 is 52136101111312.

It is a happy number.

It can be written as a sum of positive squares in 20 ways, for example, as 21308868519409 + 2241643716 = 4616153^2 + 47346^2 .

It is not a de Polignac number, because 21311110163125 - 2⁹ = 21311110162613 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21311110163093 and 21311110163102.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1784694655 + ... + 1784706595.

Almost surely, 2^{21311110163125} is an apocalyptic number.

21311110163125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21311110163125 is a deficient number, since it is larger than the sum of its proper divisors (5391648037763).

21311110163125 is an equidigital number, since it uses as much as digits as its factorization.

21311110163125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19483 (or 19468 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 28.

Adding to 21311110163125 its reverse (52136101111312), we get a palindrome (73447211274437).

The spelling of 21311110163125 in words is "twenty-one trillion, three hundred eleven billion, one hundred ten million, one hundred sixty-three thousand, one hundred twenty-five".