1666739085264 has 800 divisors, whose sum is σ = 5567026544640. Its totient is φ = 480797856000.

The previous prime is 1666739085259. The next prime is 1666739085287. The reversal of 1666739085264 is 4625809376661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 3796671957 + ... + 3796672395.

It is a 1-persistent number, because it is pandigital, but 2⋅1666739085264 = 3333478170528 is not.

Almost surely, 2^{1666739085264} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1666739085264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2783513272320).

1666739085264 is an abundant number, since it is smaller than the sum of its proper divisors (3900287459376).

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

1666739085264 is a wasteful number, since it uses less digits than its factorization.

1666739085264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 594 (or 557 counting only the distinct ones).

The product of its (nonzero) digits is 78382080, while the sum is 63.

The spelling of 1666739085264 in words is "one trillion, six hundred sixty-six billion, seven hundred thirty-nine million, eighty-five thousand, two hundred sixty-four".