20999306 has 16 divisors (see below), whose sum is σ = 33004800. Its totient is φ = 10007088.

The previous prime is 20999273. The next prime is 20999317. The reversal of 20999306 is 60399902.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20999306.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2291 + ... + 6873.

It is an arithmetic number, because the mean of its divisors is an integer number (2062800).

Almost surely, 2^20999306 is an apocalyptic number.

It is a pronic number, being equal to 4582×4583.

20999306 is a deficient number, since it is larger than the sum of its proper divisors (12005494).

20999306 is a wasteful number, since it uses less digits than its factorization.

20999306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4693.

The product of its (nonzero) digits is 26244, while the sum is 38.

The square root of 20999306 is about 4582.4999727223. The cubic root of 20999306 is about 275.8893784088.

The spelling of 20999306 in words is "twenty million, nine hundred ninety-nine thousand, three hundred six".