20099857 has 2 divisors, whose sum is σ = 20099858. Its totient is φ = 20099856.

The previous prime is 20099839. The next prime is 20099867. The reversal of 20099857 is 75899002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20061441 + 38416 = 4479^2 + 196^2 .

It is a cyclic number.

It is not a de Polignac number, because 20099857 - 2¹¹ = 20097809 is a prime.

It is not a weakly prime, because it can be changed into another prime (20099867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10049928 + 10049929.

It is an arithmetic number, because the mean of its divisors is an integer number (10049929).

Almost surely, 2^20099857 is an apocalyptic number.

It is an amenable number.

20099857 is a deficient number, since it is larger than the sum of its proper divisors (1).

20099857 is an equidigital number, since it uses as much as digits as its factorization.

20099857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45360, while the sum is 40.

The square root of 20099857 is about 4483.2864061980. The cubic root of 20099857 is about 271.8927678880.

The spelling of 20099857 in words is "twenty million, ninety-nine thousand, eight hundred fifty-seven".