18861856 has 24 divisors (see below), whose sum is σ = 39991644. Its totient is φ = 8705280.

The previous prime is 18861827. The next prime is 18861881. The reversal of 18861856 is 65816881.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 13571856 + 5290000 = 3684^2 + 2300^2 .

It is a super-2 number, since 2×18861856² = 711539223529472, which contains 22 as substring.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 22255 + ... + 23086.

Almost surely, 2^18861856 is an apocalyptic number.

18861856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18861856 is an abundant number, since it is smaller than the sum of its proper divisors (21129788).

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

18861856 is a wasteful number, since it uses less digits than its factorization.

18861856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45364 (or 45356 counting only the distinct ones).

The product of its digits is 92160, while the sum is 43.

The square root of 18861856 is about 4343.0238313875. The cubic root of 18861856 is about 266.1918829561.

The spelling of 18861856 in words is "eighteen million, eight hundred sixty-one thousand, eight hundred fifty-six".