20122809 has 16 divisors (see below), whose sum is σ = 30748032. Its totient is φ = 11467008.

The previous prime is 20122807. The next prime is 20122819. The reversal of 20122809 is 90822102.

It is not a de Polignac number, because 20122809 - 2¹ = 20122807 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20122807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7987 + ... + 10199.

It is an arithmetic number, because the mean of its divisors is an integer number (1921752).

Almost surely, 2^20122809 is an apocalyptic number.

It is an amenable number.

20122809 is a deficient number, since it is larger than the sum of its proper divisors (10625223).

20122809 is a wasteful number, since it uses less digits than its factorization.

20122809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2656.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 20122809 is about 4485.8454052720. The cubic root of 20122809 is about 271.9962198509.

The spelling of 20122809 in words is "twenty million, one hundred twenty-two thousand, eight hundred nine".