1666773636 has 96 divisors (see below), whose sum is σ = 4522936320. Its totient is φ = 472128000.

The previous prime is 1666773623. The next prime is 1666773649. The reversal of 1666773636 is 6363776661.

It is an interprime number because it is at equal distance from previous prime (1666773623) and next prime (1666773649).

It is a Harshad number since it is a multiple of its sum of digits (51).

Its product of digits (3429216) is a multiple of the sum of its prime divisors (5103).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 336385 + ... + 341303.

It is an arithmetic number, because the mean of its divisors is an integer number (47113920).

Almost surely, 2^1666773636 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 1666773636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2261468160).

1666773636 is an abundant number, since it is smaller than the sum of its proper divisors (2856162684).

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

1666773636 is a wasteful number, since it uses less digits than its factorization.

1666773636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5105 (or 5103 counting only the distinct ones).

The product of its digits is 3429216, while the sum is 51.

The square root of 1666773636 is about 40826.1391267898. The cubic root of 1666773636 is about 1185.6564661877.

The spelling of 1666773636 in words is "one billion, six hundred sixty-six million, seven hundred seventy-three thousand, six hundred thirty-six".