21023313313 has 4 divisors (see below), whose sum is σ = 22259978820. Its totient is φ = 19786647808.

The previous prime is 21023313301. The next prime is 21023313319. The reversal of 21023313313 is 31331332012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10425022609 + 10598290704 = 102103^2 + 102948^2 .

It is a cyclic number.

It is not a de Polignac number, because 21023313313 - 2⁹ = 21023312801 is a prime.

It is a super-3 number, since 3×21023313313³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21023313319) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 618332728 + ... + 618332761.

It is an arithmetic number, because the mean of its divisors is an integer number (5564994705).

Almost surely, 2^21023313313 is an apocalyptic number.

It is an amenable number.

21023313313 is a deficient number, since it is larger than the sum of its proper divisors (1236665507).

21023313313 is a wasteful number, since it uses less digits than its factorization.

21023313313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1236665506.

The product of its (nonzero) digits is 972, while the sum is 22.

Adding to 21023313313 its reverse (31331332012), we get a palindrome (52354645325).

The spelling of 21023313313 in words is "twenty-one billion, twenty-three million, three hundred thirteen thousand, three hundred thirteen".