20368909 has 4 divisors (see below), whose sum is σ = 22220640. Its totient is φ = 18517180.

The previous prime is 20368903. The next prime is 20368913. The reversal of 20368909 is 90986302.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20368909 - 2⁵ = 20368877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20368903) 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 in 3 ways as a sum of consecutive naturals, for example, 925849 + ... + 925870.

It is an arithmetic number, because the mean of its divisors is an integer number (5555160).

Almost surely, 2^20368909 is an apocalyptic number.

It is an amenable number.

20368909 is a deficient number, since it is larger than the sum of its proper divisors (1851731).

20368909 is a wasteful number, since it uses less digits than its factorization.

20368909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1851730.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 20368909 is about 4513.1927723065. The cubic root of 20368909 is about 273.1005591431.

The spelling of 20368909 in words is "twenty million, three hundred sixty-eight thousand, nine hundred nine".