21052039 has 2 divisors, whose sum is σ = 21052040. Its totient is φ = 21052038.

The previous prime is 21051991. The next prime is 21052043. The reversal of 21052039 is 93025012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21052039 - 2¹⁷ = 20920967 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 (21052049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10526019 + 10526020.

It is an arithmetic number, because the mean of its divisors is an integer number (10526020).

Almost surely, 2^21052039 is an apocalyptic number.

21052039 is a deficient number, since it is larger than the sum of its proper divisors (1).

21052039 is an equidigital number, since it uses as much as digits as its factorization.

21052039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 21052039 is about 4588.2501021631. The cubic root of 21052039 is about 276.1201211710.

The spelling of 21052039 in words is "twenty-one million, fifty-two thousand, thirty-nine".