21273703 has 4 divisors (see below), whose sum is σ = 23207688. Its totient is φ = 19339720.

The previous prime is 21273683. The next prime is 21273709. The reversal of 21273703 is 30737212.

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 21273703 - 2⁹ = 21273191 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 (21273709) 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, 966976 + ... + 966997.

It is an arithmetic number, because the mean of its divisors is an integer number (5801922).

Almost surely, 2^21273703 is an apocalyptic number.

21273703 is a deficient number, since it is larger than the sum of its proper divisors (1933985).

21273703 is a wasteful number, since it uses less digits than its factorization.

21273703 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1933984.

The product of its (nonzero) digits is 1764, while the sum is 25.

The square root of 21273703 is about 4612.3424634344. The cubic root of 21273703 is about 277.0858600758.

The spelling of 21273703 in words is "twenty-one million, two hundred seventy-three thousand, seven hundred three".