20646004220 has 24 divisors (see below), whose sum is σ = 44851665600. Its totient is φ = 7973628992.

The previous prime is 20646004217. The next prime is 20646004231. The reversal of 20646004220 is 2240064602.

It is a self number, because there is not a number n which added to its sum of digits gives 20646004220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17797700 + ... + 17798859.

It is an arithmetic number, because the mean of its divisors is an integer number (1868819400).

Almost surely, 2^20646004220 is an apocalyptic number.

20646004220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20646004220 is an abundant number, since it is smaller than the sum of its proper divisors (24205661380).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20646004220 is a wasteful number, since it uses less digits than its factorization.

20646004220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35596597 (or 35596595 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 20646004220 its reverse (2240064602), we get a palindrome (22886068822).

The spelling of 20646004220 in words is "twenty billion, six hundred forty-six million, four thousand, two hundred twenty".