20099689 has 2 divisors, whose sum is σ = 20099690. Its totient is φ = 20099688.

The previous prime is 20099633. The next prime is 20099719. The reversal of 20099689 is 98699002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12482089 + 7617600 = 3533^2 + 2760^2 .

It is a cyclic number.

It is not a de Polignac number, because 20099689 - 2¹⁹ = 19575401 is a prime.

It is not a weakly prime, because it can be changed into another prime (20099089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10049844 + 10049845.

It is an arithmetic number, because the mean of its divisors is an integer number (10049845).

Almost surely, 2^20099689 is an apocalyptic number.

It is an amenable number.

20099689 is a deficient number, since it is larger than the sum of its proper divisors (1).

20099689 is an equidigital number, since it uses as much as digits as its factorization.

20099689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 20099689 is about 4483.2676699033. The cubic root of 20099689 is about 271.8920103683.

The spelling of 20099689 in words is "twenty million, ninety-nine thousand, six hundred eighty-nine".