20391384 has 32 divisors (see below), whose sum is σ = 54900720. Its totient is φ = 6274176.

The previous prime is 20391377. The next prime is 20391407. The reversal of 20391384 is 48319302.

It is a super-3 number, since 3×20391384³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 32367 + ... + 32990.

Almost surely, 2^20391384 is an apocalyptic number.

20391384 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20391384 is an abundant number, since it is smaller than the sum of its proper divisors (34509336).

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

20391384 is a wasteful number, since it uses less digits than its factorization.

20391384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65379 (or 65375 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 20391384 is about 4515.6820082907. The cubic root of 20391384 is about 273.2009683652.

The spelling of 20391384 in words is "twenty million, three hundred ninety-one thousand, three hundred eighty-four".