21117703 has 4 divisors (see below), whose sum is σ = 22035888. Its totient is φ = 20199520.

The previous prime is 21117697. The next prime is 21117709. The reversal of 21117703 is 30771112.

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

It is an interprime number because it is at equal distance from previous prime (21117697) and next prime (21117709).

It is not a de Polignac number, because 21117703 - 2⁵ = 21117671 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21117709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 459058 + ... + 459103.

It is an arithmetic number, because the mean of its divisors is an integer number (5508972).

Almost surely, 2^21117703 is an apocalyptic number.

21117703 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21117703 is a deficient number, since it is larger than the sum of its proper divisors (918185).

21117703 is an equidigital number, since it uses as much as digits as its factorization.

21117703 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 918184.

The product of its (nonzero) digits is 294, while the sum is 22.

The square root of 21117703 is about 4595.4002002002. The cubic root of 21117703 is about 276.4069078509.

Adding to 21117703 its reverse (30771112), we get a palindrome (51888815).

The spelling of 21117703 in words is "twenty-one million, one hundred seventeen thousand, seven hundred three".