20731328 has 14 divisors (see below), whose sum is σ = 41138856. Its totient is φ = 10365632.

The previous prime is 20731327. The next prime is 20731339. The reversal of 20731328 is 82313702.

It is a junction number, because it is equal to n+sod(n) for n = 20731297 and 20731306.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161900 + ... + 162027.

Almost surely, 2^20731328 is an apocalyptic number.

It is an amenable number.

20731328 is a deficient number, since it is larger than the sum of its proper divisors (20407528).

20731328 is an equidigital number, since it uses as much as digits as its factorization.

20731328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323939 (or 323929 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 20731328 is about 4553.1668100345. The cubic root of 20731328 is about 274.7107835421.

The spelling of 20731328 in words is "twenty million, seven hundred thirty-one thousand, three hundred twenty-eight".