21920343 has 4 divisors (see below), whose sum is σ = 29227128. Its totient is φ = 14613560.

The previous prime is 21920321. The next prime is 21920359. The reversal of 21920343 is 34302912.

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 21920343 - 2⁶ = 21920279 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21920443) 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, 3653388 + ... + 3653393.

It is an arithmetic number, because the mean of its divisors is an integer number (7306782).

Almost surely, 2^21920343 is an apocalyptic number.

21920343 is a deficient number, since it is larger than the sum of its proper divisors (7306785).

21920343 is an equidigital number, since it uses as much as digits as its factorization.

21920343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7306784.

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 21920343 is about 4681.9165947291. The cubic root of 21920343 is about 279.8653391593.

The spelling of 21920343 in words is "twenty-one million, nine hundred twenty thousand, three hundred forty-three".