21231121313 has 8 divisors (see below), whose sum is σ = 23457403008. Its totient is φ = 19113438784.

The previous prime is 21231121259. The next prime is 21231121333. The reversal of 21231121313 is 31312113212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21231121313 - 2¹² = 21231117217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21231121333) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27149381 + ... + 27150162.

It is an arithmetic number, because the mean of its divisors is an integer number (2932175376).

Almost surely, 2^21231121313 is an apocalyptic number.

21231121313 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21231121313 is a deficient number, since it is larger than the sum of its proper divisors (2226281695).

21231121313 is a wasteful number, since it uses less digits than its factorization.

21231121313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54299583.

The product of its digits is 216, while the sum is 20.

Adding to 21231121313 its reverse (31312113212), we get a palindrome (52543234525).

The spelling of 21231121313 in words is "twenty-one billion, two hundred thirty-one million, one hundred twenty-one thousand, three hundred thirteen".