21101031313 has 8 divisors (see below), whose sum is σ = 21151915560. Its totient is φ = 21050209920.

The previous prime is 21101031293. The next prime is 21101031323. The reversal of 21101031313 is 31313010112.

It can be written as a sum of positive squares in 4 ways, for example, as 15342042769 + 5758988544 = 123863^2 + 75888^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21101031313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21101031323) 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, 694623 + ... + 724363.

It is an arithmetic number, because the mean of its divisors is an integer number (2643989445).

Almost surely, 2^21101031313 is an apocalyptic number.

It is an amenable number.

21101031313 is a deficient number, since it is larger than the sum of its proper divisors (50884247).

21101031313 is an equidigital number, since it uses as much as digits as its factorization.

21101031313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31427.

The product of its (nonzero) digits is 54, while the sum is 16.

Adding to 21101031313 its reverse (31313010112), we get a palindrome (52414041425).

The spelling of 21101031313 in words is "twenty-one billion, one hundred one million, thirty-one thousand, three hundred thirteen".