18630861 has 16 divisors (see below), whose sum is σ = 26396928. Its totient is φ = 11648000.

The previous prime is 18630853. The next prime is 18630863. The reversal of 18630861 is 16803681.

It is a cyclic number.

It is not a de Polignac number, because 18630861 - 2³ = 18630853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18630863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19996 + ... + 20906.

It is an arithmetic number, because the mean of its divisors is an integer number (1649808).

Almost surely, 2^18630861 is an apocalyptic number.

It is an amenable number.

18630861 is a deficient number, since it is larger than the sum of its proper divisors (7766067).

18630861 is a wasteful number, since it uses less digits than its factorization.

18630861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1332.

The product of its (nonzero) digits is 6912, while the sum is 33.

The square root of 18630861 is about 4316.3481092238. The cubic root of 18630861 is about 265.1007614925.

It can be divided in two parts, 18630 and 861, that added together give a palindrome (19491).

The spelling of 18630861 in words is "eighteen million, six hundred thirty thousand, eight hundred sixty-one".