21050339 has 2 divisors, whose sum is σ = 21050340. Its totient is φ = 21050338.

The previous prime is 21050311. The next prime is 21050357. The reversal of 21050339 is 93305012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21050339 - 2²⁰ = 20001763 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21050399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10525169 + 10525170.

It is an arithmetic number, because the mean of its divisors is an integer number (10525170).

Almost surely, 2^21050339 is an apocalyptic number.

21050339 is a deficient number, since it is larger than the sum of its proper divisors (1).

21050339 is an equidigital number, since it uses as much as digits as its factorization.

21050339 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 810, while the sum is 23.

The square root of 21050339 is about 4588.0648426107. The cubic root of 21050339 is about 276.1126885285.

Subtracting from 21050339 its sum of digits (23), we obtain a triangular number (21050316 = T₆₄₈₈).

The spelling of 21050339 in words is "twenty-one million, fifty thousand, three hundred thirty-nine".