21220021103 has 4 divisors (see below), whose sum is σ = 21232169400. Its totient is φ = 21207872808.

The previous prime is 21220021073. The next prime is 21220021157. The reversal of 21220021103 is 30112002212.

It is a happy number.

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 21220021103 - 2²² = 21215826799 is a prime.

It is a super-2 number, since 2×21220021103² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220021003) 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, 6071528 + ... + 6075021.

It is an arithmetic number, because the mean of its divisors is an integer number (5308042350).

Almost surely, 2^21220021103 is an apocalyptic number.

21220021103 is a deficient number, since it is larger than the sum of its proper divisors (12148297).

21220021103 is a wasteful number, since it uses less digits than its factorization.

21220021103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12148296.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21220021103 its reverse (30112002212), we get a palindrome (51332023315).

The spelling of 21220021103 in words is "twenty-one billion, two hundred twenty million, twenty-one thousand, one hundred three".