1666412786500 has 288 divisors, whose sum is σ = 4617249960960. Its totient is φ = 514245600000.

The previous prime is 1666412786497. The next prime is 1666412786501. The reversal of 1666412786500 is 56872146661.

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1666412786501) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 42754021 + ... + 42792979.

It is an arithmetic number, because the mean of its divisors is an integer number (16032117920).

Almost surely, 2^{1666412786500} is an apocalyptic number.

1666412786500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1666412786500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2308624980480).

1666412786500 is an abundant number, since it is smaller than the sum of its proper divisors (2950837174460).

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

1666412786500 is a wasteful number, since it uses less digits than its factorization.

1666412786500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39108 (or 39085 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 52.

The spelling of 1666412786500 in words is "one trillion, six hundred sixty-six billion, four hundred twelve million, seven hundred eighty-six thousand, five hundred".