16929821 has 2 divisors, whose sum is σ = 16929822. Its totient is φ = 16929820.

The previous prime is 16929799. The next prime is 16929877. The reversal of 16929821 is 12892961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11222500 + 5707321 = 3350^2 + 2389^2 .

It is a cyclic number.

It is not a de Polignac number, because 16929821 - 2¹⁰ = 16928797 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16929421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8464910 + 8464911.

It is an arithmetic number, because the mean of its divisors is an integer number (8464911).

Almost surely, 2^16929821 is an apocalyptic number.

It is an amenable number.

16929821 is a deficient number, since it is larger than the sum of its proper divisors (1).

16929821 is an equidigital number, since it uses as much as digits as its factorization.

16929821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 38.

The square root of 16929821 is about 4114.5863704630. The cubic root of 16929821 is about 256.7738475921.

The spelling of 16929821 in words is "sixteen million, nine hundred twenty-nine thousand, eight hundred twenty-one".