16721039 has 2 divisors, whose sum is σ = 16721040. Its totient is φ = 16721038.

The previous prime is 16721027. The next prime is 16721041. The reversal of 16721039 is 93012761.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16721039 - 2¹² = 16716943 is a prime.

Together with 16721041, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16721009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8360519 + 8360520.

It is an arithmetic number, because the mean of its divisors is an integer number (8360520).

Almost surely, 2^16721039 is an apocalyptic number.

16721039 is a deficient number, since it is larger than the sum of its proper divisors (1).

16721039 is an equidigital number, since it uses as much as digits as its factorization.

16721039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 16721039 is about 4089.1367059564. The cubic root of 16721039 is about 255.7139494928.

The spelling of 16721039 in words is "sixteen million, seven hundred twenty-one thousand, thirty-nine".