1666939647880 has 64 divisors (see below), whose sum is σ = 4052280133440. Its totient is φ = 613480511232.

The previous prime is 1666939647871. The next prime is 1666939647883. The reversal of 1666939647880 is 887469396661.

It is not an unprimeable number, because it can be changed into a prime (1666939647883) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5061294 + ... + 5380573.

It is an arithmetic number, because the mean of its divisors is an integer number (63316877085).

Almost surely, 2^{1666939647880} is an apocalyptic number.

1666939647880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1666939647880 is an abundant number, since it is smaller than the sum of its proper divisors (2385340485560).

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

1666939647880 is a wasteful number, since it uses less digits than its factorization.

1666939647880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10442198 (or 10442194 counting only the distinct ones).

The product of its (nonzero) digits is 564350976, while the sum is 73.

The spelling of 1666939647880 in words is "one trillion, six hundred sixty-six billion, nine hundred thirty-nine million, six hundred forty-seven thousand, eight hundred eighty".