21039703 has 4 divisors (see below), whose sum is σ = 21765240. Its totient is φ = 20314168.

The previous prime is 21039701. The next prime is 21039719. The reversal of 21039703 is 30793012.

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 21039703 - 2¹ = 21039701 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 (21039701) 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, 362725 + ... + 362782.

It is an arithmetic number, because the mean of its divisors is an integer number (5441310).

Almost surely, 2^21039703 is an apocalyptic number.

21039703 is a deficient number, since it is larger than the sum of its proper divisors (725537).

21039703 is an equidigital number, since it uses as much as digits as its factorization.

21039703 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 725536.

The product of its (nonzero) digits is 1134, while the sum is 25.

The square root of 21039703 is about 4586.9056018192. The cubic root of 21039703 is about 276.0661773329.

The spelling of 21039703 in words is "twenty-one million, thirty-nine thousand, seven hundred three".