6664840426660 has 24 divisors (see below), whose sum is σ = 15072792965496. Its totient is φ = 2460864157440.

The previous prime is 6664840426649. The next prime is 6664840426661. The reversal of 6664840426660 is 666240484666.

It can be written as a sum of positive squares in 4 ways, for example, as 209622959716 + 6455217466944 = 457846^2 + 2540712^2 .

It is a junction number, because it is equal to n+sod(n) for n = 6664840426595 and 6664840426604.

It is not an unprimeable number, because it can be changed into a prime (6664840426661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12817000561 + ... + 12817001080.

It is an arithmetic number, because the mean of its divisors is an integer number (628033040229).

Almost surely, 2^{6664840426660} is an apocalyptic number.

It is an amenable number.

6664840426660 is an abundant number, since it is smaller than the sum of its proper divisors (8407952538836).

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

6664840426660 is a wasteful number, since it uses less digits than its factorization.

6664840426660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25634001663 (or 25634001661 counting only the distinct ones).

The product of its (nonzero) digits is 47775744, while the sum is 58.

The spelling of 6664840426660 in words is "six trillion, six hundred sixty-four billion, eight hundred forty million, four hundred twenty-six thousand, six hundred sixty".