21103333331 has 4 divisors (see below), whose sum is σ = 21103691952. Its totient is φ = 21102974712.

The previous prime is 21103333309. The next prime is 21103333369. The reversal of 21103333331 is 13333330112.

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

It is a cyclic number.

It is not a de Polignac number, because 21103333331 - 2¹⁴ = 21103316947 is a prime.

It is a super-2 number, since 2×21103333331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21103333297 and 21103333306.

It is not an unprimeable number, because it can be changed into a prime (21103333301) 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, 68015 + ... + 216408.

It is an arithmetic number, because the mean of its divisors is an integer number (5275922988).

Almost surely, 2^21103333331 is an apocalyptic number.

21103333331 is a deficient number, since it is larger than the sum of its proper divisors (358621).

21103333331 is an equidigital number, since it uses as much as digits as its factorization.

21103333331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358620.

The product of its (nonzero) digits is 1458, while the sum is 23.

Adding to 21103333331 its reverse (13333330112), we get a palindrome (34436663443).

The spelling of 21103333331 in words is "twenty-one billion, one hundred three million, three hundred thirty-three thousand, three hundred thirty-one".