20320999 has 2 divisors, whose sum is σ = 20321000. Its totient is φ = 20320998.

The previous prime is 20320987. The next prime is 20321003. The reversal of 20320999 is 99902302.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20320999 - 2¹⁷ = 20189927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20320919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10160499 + 10160500.

It is an arithmetic number, because the mean of its divisors is an integer number (10160500).

Almost surely, 2^20320999 is an apocalyptic number.

20320999 is a deficient number, since it is larger than the sum of its proper divisors (1).

20320999 is an equidigital number, since it uses as much as digits as its factorization.

20320999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 20320999 is about 4507.8818751161. The cubic root of 20320999 is about 272.8862698103.

The spelling of 20320999 in words is "twenty million, three hundred twenty thousand, nine hundred ninety-nine".