21397103 has 16 divisors (see below), whose sum is σ = 26703936. Its totient is φ = 16692480.

The previous prime is 21397093. The next prime is 21397139. The reversal of 21397103 is 30179312.

It is not a de Polignac number, because 21397103 - 2¹⁶ = 21331567 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21397303) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5033 + ... + 8253.

It is an arithmetic number, because the mean of its divisors is an integer number (1668996).

Almost surely, 2^21397103 is an apocalyptic number.

21397103 is a deficient number, since it is larger than the sum of its proper divisors (5306833).

21397103 is a wasteful number, since it uses less digits than its factorization.

21397103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3314.

The product of its (nonzero) digits is 1134, while the sum is 26.

The square root of 21397103 is about 4625.7002713103. The cubic root of 21397103 is about 277.6205812032.

The spelling of 21397103 in words is "twenty-one million, three hundred ninety-seven thousand, one hundred three".