18783666 has 48 divisors (see below), whose sum is σ = 46743840. Its totient is φ = 5391360.

The previous prime is 18783641. The next prime is 18783671. The reversal of 18783666 is 66638781.

It is a super-2 number, since 2×18783666² = 705652216799112, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1266 + ... + 6258.

It is an arithmetic number, because the mean of its divisors is an integer number (973830).

Almost surely, 2^18783666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18783666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23371920).

18783666 is an abundant number, since it is smaller than the sum of its proper divisors (27960174).

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

18783666 is a wasteful number, since it uses less digits than its factorization.

18783666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5031 (or 5028 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 18783666 is about 4334.0126903368. The cubic root of 18783666 is about 265.8235492862.

The spelling of 18783666 in words is "eighteen million, seven hundred eighty-three thousand, six hundred sixty-six".