18863816 has 8 divisors (see below), whose sum is σ = 35369670. Its totient is φ = 9431904.

The previous prime is 18863809. The next prime is 18863839. The reversal of 18863816 is 61836881.

It can be written as a sum of positive squares in only one way, i.e., 13322500 + 5541316 = 3650^2 + 2354^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1178981 + ... + 1178996.

Almost surely, 2^18863816 is an apocalyptic number.

It is an amenable number.

18863816 is a deficient number, since it is larger than the sum of its proper divisors (16505854).

18863816 is a wasteful number, since it uses less digits than its factorization.

18863816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2357983 (or 2357979 counting only the distinct ones).

The product of its digits is 55296, while the sum is 41.

The square root of 18863816 is about 4343.2494747597. The cubic root of 18863816 is about 266.2011029399.

The spelling of 18863816 in words is "eighteen million, eight hundred sixty-three thousand, eight hundred sixteen".