20665646620620 has 96 divisors (see below), whose sum is σ = 58336665004800. Its totient is φ = 5465963645184.

The previous prime is 20665646620579. The next prime is 20665646620649. The reversal of 20665646620620 is 2602664656602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1704627 + ... + 6651093.

It is an arithmetic number, because the mean of its divisors is an integer number (607673593800).

Almost surely, 2^{20665646620620} is an apocalyptic number.

20665646620620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20665646620620 is an abundant number, since it is smaller than the sum of its proper divisors (37671018384180).

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

20665646620620 is a wasteful number, since it uses less digits than its factorization.

20665646620620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4947047 (or 4947045 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 51.

The spelling of 20665646620620 in words is "twenty trillion, six hundred sixty-five billion, six hundred forty-six million, six hundred twenty thousand, six hundred twenty".