20605099 has 2 divisors, whose sum is σ = 20605100. Its totient is φ = 20605098.

The previous prime is 20605073. The next prime is 20605147. The reversal of 20605099 is 99050602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20605099 - 2¹⁹ = 20080811 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20605099.

It is not a weakly prime, because it can be changed into another prime (20605019) 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, 10302549 + 10302550.

It is an arithmetic number, because the mean of its divisors is an integer number (10302550).

Almost surely, 2^20605099 is an apocalyptic number.

20605099 is a deficient number, since it is larger than the sum of its proper divisors (1).

20605099 is an equidigital number, since it uses as much as digits as its factorization.

20605099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 20605099 is about 4539.2839743731. The cubic root of 20605099 is about 274.1520946833.

It can be divided in two parts, 2060509 and 9, that multiplied together give a palindrome (18544581).

The spelling of 20605099 in words is "twenty million, six hundred five thousand, ninety-nine".