21046223 has 4 divisors (see below), whose sum is σ = 22959528. Its totient is φ = 19132920.

The previous prime is 21046217. The next prime is 21046231. The reversal of 21046223 is 32264012.

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 21046223 - 2¹² = 21042127 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21046195 and 21046204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21046253) 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, 956636 + ... + 956657.

It is an arithmetic number, because the mean of its divisors is an integer number (5739882).

Almost surely, 2^21046223 is an apocalyptic number.

21046223 is a deficient number, since it is larger than the sum of its proper divisors (1913305).

21046223 is a wasteful number, since it uses less digits than its factorization.

21046223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1913304.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 21046223 is about 4587.6162655567. The cubic root of 21046223 is about 276.0946911318.

The spelling of 21046223 in words is "twenty-one million, forty-six thousand, two hundred twenty-three".