18973836 has 144 divisors (see below), whose sum is σ = 59963904. Its totient is φ = 4935168.

The previous prime is 18973831. The next prime is 18973897. The reversal of 18973836 is 63837981.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 18973791 and 18973800.

It is not an unprimeable number, because it can be changed into a prime (18973831) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 184161 + ... + 184263.

It is an arithmetic number, because the mean of its divisors is an integer number (416416).

Almost surely, 2^18973836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18973836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29981952).

18973836 is an abundant number, since it is smaller than the sum of its proper divisors (40990068).

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

18973836 is a wasteful number, since it uses less digits than its factorization.

18973836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 175 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 18973836 is about 4355.8966929899. The cubic root of 18973836 is about 266.7176242896.

The spelling of 18973836 in words is "eighteen million, nine hundred seventy-three thousand, eight hundred thirty-six".