18943866 has 12 divisors (see below), whose sum is σ = 41045082. Its totient is φ = 6314616.

The previous prime is 18943853. The next prime is 18943871. The reversal of 18943866 is 66834981.

It can be written as a sum of positive squares in only one way, i.e., 13111641 + 5832225 = 3621^2 + 2415^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 526201 + ... + 526236.

Almost surely, 2^18943866 is an apocalyptic number.

18943866 is an abundant number, since it is smaller than the sum of its proper divisors (22101216).

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

18943866 is a wasteful number, since it uses less digits than its factorization.

18943866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1052445 (or 1052442 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 18943866 is about 4352.4551692120. The cubic root of 18943866 is about 266.5771195861.

The spelling of 18943866 in words is "eighteen million, nine hundred forty-three thousand, eight hundred sixty-six".