20446609 has 4 divisors (see below), whose sum is σ = 21335616. Its totient is φ = 19557604.

The previous prime is 20446583. The next prime is 20446649. The reversal of 20446609 is 90664402.

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, and also an emirpimes, since its reverse is a distinct semiprime: 90664402 = 2 ⋅45332201.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20446609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20446649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 444469 + ... + 444514.

It is an arithmetic number, because the mean of its divisors is an integer number (5333904).

Almost surely, 2^20446609 is an apocalyptic number.

It is an amenable number.

20446609 is a deficient number, since it is larger than the sum of its proper divisors (889007).

20446609 is an equidigital number, since it uses as much as digits as its factorization.

20446609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 889006.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 20446609 is about 4521.7926754773. The cubic root of 20446609 is about 273.4473783794.

The spelling of 20446609 in words is "twenty million, four hundred forty-six thousand, six hundred nine".