18401856 has 56 divisors (see below), whose sum is σ = 53120544. Its totient is φ = 5575680.

The previous prime is 18401849. The next prime is 18401857. The reversal of 18401856 is 65810481.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18401857) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2245 + ... + 6468.

Almost surely, 2^18401856 is an apocalyptic number.

18401856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18401856 is an abundant number, since it is smaller than the sum of its proper divisors (34718688).

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

18401856 is a wasteful number, since it uses less digits than its factorization.

18401856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8739 (or 8729 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 33.

The square root of 18401856 is about 4289.7384535657. The cubic root of 18401856 is about 264.0101006236.

The spelling of 18401856 in words is "eighteen million, four hundred one thousand, eight hundred fifty-six".