6660566620 has 24 divisors (see below), whose sum is σ = 14093967888. Its totient is φ = 2643888000.

The previous prime is 6660566617. The next prime is 6660566621. The reversal of 6660566620 is 266650666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6660566621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1268481 + ... + 1273720.

It is an arithmetic number, because the mean of its divisors is an integer number (587248662).

Almost surely, 2^6660566620 is an apocalyptic number.

It is an amenable number.

6660566620 is an abundant number, since it is smaller than the sum of its proper divisors (7433401268).

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

6660566620 is a wasteful number, since it uses less digits than its factorization.

6660566620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2542341 (or 2542339 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 43.

The square root of 6660566620 is about 81612.2945394871. The cubic root of 6660566620 is about 1881.4978462215.

It can be divided in two parts, 66605 and 66620, that added together give a square (133225 = 365²).

The spelling of 6660566620 in words is "six billion, six hundred sixty million, five hundred sixty-six thousand, six hundred twenty".