18321536 has 16 divisors (see below), whose sum is σ = 36500190. Its totient is φ = 9160704.

The previous prime is 18321521. The next prime is 18321539. The reversal of 18321536 is 63512381.

It can be written as a sum of positive squares in only one way, i.e., 18318400 + 3136 = 4280^2 + 56^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a junction number, because it is equal to n+sod(n) for n = 18321499 and 18321508.

It is not an unprimeable number, because it can be changed into a prime (18321539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71441 + ... + 71696.

Almost surely, 2^18321536 is an apocalyptic number.

18321536 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18321536 is a deficient number, since it is larger than the sum of its proper divisors (18178654).

18321536 is an equidigital number, since it uses as much as digits as its factorization.

18321536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143151 (or 143139 counting only the distinct ones).

The product of its digits is 4320, while the sum is 29.

The square root of 18321536 is about 4280.3663394621. The cubic root of 18321536 is about 263.6254253236.

The spelling of 18321536 in words is "eighteen million, three hundred twenty-one thousand, five hundred thirty-six".