18121936 has 40 divisors (see below), whose sum is σ = 40354560. Its totient is φ = 7722624.

The previous prime is 18121921. The next prime is 18121973. The reversal of 18121936 is 63912181.

It is a junction number, because it is equal to n+sod(n) for n = 18121898 and 18121907.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26430 + ... + 27106.

It is an arithmetic number, because the mean of its divisors is an integer number (1008864).

Almost surely, 2^18121936 is an apocalyptic number.

18121936 is a gapful number since it is divisible by the number (16) 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 18121936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20177280).

18121936 is an abundant number, since it is smaller than the sum of its proper divisors (22232624).

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

18121936 is a wasteful number, since it uses less digits than its factorization.

18121936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 931 (or 925 counting only the distinct ones).

The product of its digits is 2592, while the sum is 31.

The square root of 18121936 is about 4256.9867277219. The cubic root of 18121936 is about 262.6645909576.

The spelling of 18121936 in words is "eighteen million, one hundred twenty-one thousand, nine hundred thirty-six".