18821337 has 16 divisors (see below), whose sum is σ = 26828928. Its totient is φ = 11707520.

The previous prime is 18821323. The next prime is 18821351. The reversal of 18821337 is 73312881.

It is an interprime number because it is at equal distance from previous prime (18821323) and next prime (18821351).

It is a cyclic number.

It is not a de Polignac number, because 18821337 - 2⁴ = 18821321 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 18821298 and 18821307.

It is not an unprimeable number, because it can be changed into a prime (18821137) 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 15 ways as a sum of consecutive naturals, for example, 498 + ... + 6155.

It is an arithmetic number, because the mean of its divisors is an integer number (1676808).

Almost surely, 2^18821337 is an apocalyptic number.

It is an amenable number.

18821337 is a deficient number, since it is larger than the sum of its proper divisors (8007591).

18821337 is a wasteful number, since it uses less digits than its factorization.

18821337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6720.

The product of its digits is 8064, while the sum is 33.

The square root of 18821337 is about 4338.3564860440. The cubic root of 18821337 is about 266.0011353523.

The spelling of 18821337 in words is "eighteen million, eight hundred twenty-one thousand, three hundred thirty-seven".