20409009 has 8 divisors (see below), whose sum is σ = 27392832. Its totient is φ = 13515600.

The previous prime is 20409007. The next prime is 20409013. The reversal of 20409009 is 90090402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20409009 - 2¹ = 20409007 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20409009.

It is not an unprimeable number, because it can be changed into a prime (20409001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22074 + ... + 22979.

It is an arithmetic number, because the mean of its divisors is an integer number (3424104).

Almost surely, 2^20409009 is an apocalyptic number.

It is an amenable number.

20409009 is a deficient number, since it is larger than the sum of its proper divisors (6983823).

20409009 is a wasteful number, since it uses less digits than its factorization.

20409009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45207.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 20409009 is about 4517.6331192340. The cubic root of 20409009 is about 273.2796581430.

The spelling of 20409009 in words is "twenty million, four hundred nine thousand, nine".