16039921 has 2 divisors, whose sum is σ = 16039922. Its totient is φ = 16039920.

The previous prime is 16039913. The next prime is 16039957. The reversal of 16039921 is 12993061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15210000 + 829921 = 3900^2 + 911^2 .

It is a cyclic number.

It is not a de Polignac number, because 16039921 - 2³ = 16039913 is a prime.

It is not a weakly prime, because it can be changed into another prime (16039321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8019960 + 8019961.

It is an arithmetic number, because the mean of its divisors is an integer number (8019961).

Almost surely, 2^16039921 is an apocalyptic number.

It is an amenable number.

16039921 is a deficient number, since it is larger than the sum of its proper divisors (1).

16039921 is an equidigital number, since it uses as much as digits as its factorization.

16039921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 16039921 is about 4004.9870162087. The cubic root of 16039921 is about 252.1936080393.

The spelling of 16039921 in words is "sixteen million, thirty-nine thousand, nine hundred twenty-one".