21743039 has 2 divisors, whose sum is σ = 21743040. Its totient is φ = 21743038.

The previous prime is 21743021. The next prime is 21743047. The reversal of 21743039 is 93034712.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21743039 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21743009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10871519 + 10871520.

It is an arithmetic number, because the mean of its divisors is an integer number (10871520).

Almost surely, 2^21743039 is an apocalyptic number.

21743039 is a deficient number, since it is larger than the sum of its proper divisors (1).

21743039 is an equidigital number, since it uses as much as digits as its factorization.

21743039 is an evil number, because the sum of its binary digits is even.

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

The square root of 21743039 is about 4662.9431692870. The cubic root of 21743039 is about 279.1087263532.

The spelling of 21743039 in words is "twenty-one million, seven hundred forty-three thousand, thirty-nine".