20646601 has 4 divisors (see below), whose sum is σ = 20672512. Its totient is φ = 20620692.

The previous prime is 20646581. The next prime is 20646607. The reversal of 20646601 is 10664602.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 20646601 - 2⁹ = 20646089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20646607) 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, 11721 + ... + 13366.

It is an arithmetic number, because the mean of its divisors is an integer number (5168128).

Almost surely, 2^20646601 is an apocalyptic number.

It is an amenable number.

20646601 is a deficient number, since it is larger than the sum of its proper divisors (25911).

20646601 is an equidigital number, since it uses as much as digits as its factorization.

20646601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25910.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 20646601 is about 4543.8531006185. The cubic root of 20646601 is about 274.3360334553.

The spelling of 20646601 in words is "twenty million, six hundred forty-six thousand, six hundred one".