1666290277660 has 24 divisors (see below), whose sum is σ = 3556573677216. Its totient is φ = 655589616960.

The previous prime is 1666290277637. The next prime is 1666290277661. The reversal of 1666290277660 is 667720926661.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1666290277595 and 1666290277604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666290277661) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 682904632 + ... + 682907071.

It is an arithmetic number, because the mean of its divisors is an integer number (148190569884).

Almost surely, 2^{1666290277660} is an apocalyptic number.

1666290277660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1666290277660 is an abundant number, since it is smaller than the sum of its proper divisors (1890283399556).

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

1666290277660 is a wasteful number, since it uses less digits than its factorization.

1666290277660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1365811773 (or 1365811771 counting only the distinct ones).

The product of its (nonzero) digits is 13716864, while the sum is 58.

The spelling of 1666290277660 in words is "one trillion, six hundred sixty-six billion, two hundred ninety million, two hundred seventy-seven thousand, six hundred sixty".