18971100 has 108 divisors (see below), whose sum is σ = 60324264. Its totient is φ = 4986240.

The previous prime is 18971089. The next prime is 18971107. The reversal of 18971100 is 117981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18971107) 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 35 ways as a sum of consecutive naturals, for example, 96202 + ... + 96398.

It is an arithmetic number, because the mean of its divisors is an integer number (558558).

Almost surely, 2^18971100 is an apocalyptic number.

18971100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18971100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30162132).

18971100 is an abundant number, since it is smaller than the sum of its proper divisors (41353164).

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

18971100 is a wasteful number, since it uses less digits than its factorization.

18971100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324 (or 314 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 27.

The square root of 18971100 is about 4355.5826246324. The cubic root of 18971100 is about 266.7048035734.

It can be divided in two parts, 189 and 71100, that added together give a square (71289 = 267²).

The spelling of 18971100 in words is "eighteen million, nine hundred seventy-one thousand, one hundred".