21930743 has 2 divisors, whose sum is σ = 21930744. Its totient is φ = 21930742.

The previous prime is 21930739. The next prime is 21930791. The reversal of 21930743 is 34703912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21930743 - 2² = 21930739 is a prime.

It is a Chen prime.

It is equal to p_1385138 and since 21930743 and 1385138 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21930143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10965371 + 10965372.

It is an arithmetic number, because the mean of its divisors is an integer number (10965372).

Almost surely, 2^21930743 is an apocalyptic number.

21930743 is a deficient number, since it is larger than the sum of its proper divisors (1).

21930743 is an equidigital number, since it uses as much as digits as its factorization.

21930743 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 29.

The square root of 21930743 is about 4683.0271192894. The cubic root of 21930743 is about 279.9095924106.

The spelling of 21930743 in words is "twenty-one million, nine hundred thirty thousand, seven hundred forty-three".