20403984 has 20 divisors (see below), whose sum is σ = 52710416. Its totient is φ = 6801312.

The previous prime is 20403959. The next prime is 20403989. The reversal of 20403984 is 48930402.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20403989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 212494 + ... + 212589.

Almost surely, 2^20403984 is an apocalyptic number.

20403984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20403984 is an abundant number, since it is smaller than the sum of its proper divisors (32306432).

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

20403984 is a wasteful number, since it uses less digits than its factorization.

20403984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425094 (or 425088 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 20403984 is about 4517.0769309366. The cubic root of 20403984 is about 273.2572278035.

It can be divided in two parts, 2040398 and 4, that added together give a palindrome (2040402).

The spelling of 20403984 in words is "twenty million, four hundred three thousand, nine hundred eighty-four".