20666444204220 has 48 divisors (see below), whose sum is σ = 59429990907168. Its totient is φ = 5362104441600.

The previous prime is 20666444204179. The next prime is 20666444204233. The reversal of 20666444204220 is 2240244466602.

It is a happy number.

It is a super-2 number, since 2×20666444204220² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4654602331 + ... + 4654606770.

It is an arithmetic number, because the mean of its divisors is an integer number (1238124810566).

Almost surely, 2^{20666444204220} is an apocalyptic number.

20666444204220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20666444204220 is an abundant number, since it is smaller than the sum of its proper divisors (38763546702948).

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

20666444204220 is a wasteful number, since it uses less digits than its factorization.

20666444204220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9309209150 (or 9309209148 counting only the distinct ones).

The product of its (nonzero) digits is 884736, while the sum is 42.

The spelling of 20666444204220 in words is "twenty trillion, six hundred sixty-six billion, four hundred forty-four million, two hundred four thousand, two hundred twenty".