1666504660 has 24 divisors (see below), whose sum is σ = 3505357800. Its totient is φ = 665516544.

The previous prime is 1666504657. The next prime is 1666504661. The reversal of 1666504660 is 664056661.

1666504660 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 123743376 + 1542761284 = 11124^2 + 39278^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666504661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55185 + ... + 79864.

It is an arithmetic number, because the mean of its divisors is an integer number (146056575).

Almost surely, 2^1666504660 is an apocalyptic number.

1666504660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1666504660 is an abundant number, since it is smaller than the sum of its proper divisors (1838853140).

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

1666504660 is a wasteful number, since it uses less digits than its factorization.

1666504660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135675 (or 135673 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 40.

The square root of 1666504660 is about 40822.8448298254. The cubic root of 1666504660 is about 1185.5926842234.

The spelling of 1666504660 in words is "one billion, six hundred sixty-six million, five hundred four thousand, six hundred sixty".