21043279 has 8 divisors (see below), whose sum is σ = 22569840. Its totient is φ = 19558656.

The previous prime is 21043273. The next prime is 21043289. The reversal of 21043279 is 97234012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21043279 - 2³ = 21043271 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 (21043271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9442 + ... + 11455.

It is an arithmetic number, because the mean of its divisors is an integer number (2821230).

Almost surely, 2^21043279 is an apocalyptic number.

21043279 is a deficient number, since it is larger than the sum of its proper divisors (1526561).

21043279 is a wasteful number, since it uses less digits than its factorization.

21043279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20969.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 21043279 is about 4587.2953905324. The cubic root of 21043279 is about 276.0818169188.

The spelling of 21043279 in words is "twenty-one million, forty-three thousand, two hundred seventy-nine".