18861636 has 24 divisors (see below), whose sum is σ = 46599840. Its totient is φ = 5917312.

The previous prime is 18861593. The next prime is 18861637. The reversal of 18861636 is 63616881.

It is a super-2 number, since 2×18861636² = 711522625192992, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18861594 and 18861603.

It is not an unprimeable number, because it can be changed into a prime (18861637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46026 + ... + 46433.

It is an arithmetic number, because the mean of its divisors is an integer number (1941660).

Almost surely, 2^18861636 is an apocalyptic number.

It is an amenable number.

18861636 is an abundant number, since it is smaller than the sum of its proper divisors (27738204).

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

18861636 is a wasteful number, since it uses less digits than its factorization.

18861636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92483 (or 92481 counting only the distinct ones).

The product of its digits is 41472, while the sum is 39.

The square root of 18861636 is about 4342.9985033384. The cubic root of 18861636 is about 266.1908480201.

The spelling of 18861636 in words is "eighteen million, eight hundred sixty-one thousand, six hundred thirty-six".