21021113103 has 4 divisors (see below), whose sum is σ = 28028150808. Its totient is φ = 14014075400.

The previous prime is 21021113089. The next prime is 21021113111. The reversal of 21021113103 is 30131112012.

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 21021113103 - 2¹² = 21021109007 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021113153) 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, 3503518848 + ... + 3503518853.

It is an arithmetic number, because the mean of its divisors is an integer number (7007037702).

Almost surely, 2^21021113103 is an apocalyptic number.

21021113103 is a deficient number, since it is larger than the sum of its proper divisors (7007037705).

21021113103 is an equidigital number, since it uses as much as digits as its factorization.

21021113103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7007037704.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21021113103 its reverse (30131112012), we get a palindrome (51152225115).

The spelling of 21021113103 in words is "twenty-one billion, twenty-one million, one hundred thirteen thousand, one hundred three".