21320103 has 32 divisors (see below), whose sum is σ = 34845696. Its totient is φ = 11328768.

The previous prime is 21320099. The next prime is 21320107. The reversal of 21320103 is 30102312.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21320099) and next prime (21320107).

It is not a de Polignac number, because 21320103 - 2² = 21320099 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21320107) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17275 + ... + 18467.

It is an arithmetic number, because the mean of its divisors is an integer number (1088928).

Almost surely, 2^21320103 is an apocalyptic number.

21320103 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21320103 is a deficient number, since it is larger than the sum of its proper divisors (13525593).

21320103 is a wasteful number, since it uses less digits than its factorization.

21320103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1263.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21320103 is about 4617.3697057957. The cubic root of 21320103 is about 277.2871641290.

Adding to 21320103 its reverse (30102312), we get a palindrome (51422415).

The spelling of 21320103 in words is "twenty-one million, three hundred twenty thousand, one hundred three".