20384280 has 96 divisors (see below), whose sum is σ = 75722400. Its totient is φ = 4658688.

The previous prime is 20384269. The next prime is 20384297. The reversal of 20384280 is 8248302.

20384280 is a `hidden beast` number, since 2 + 0 + 384 + 280 = 666.

It is a super-2 number, since 2×20384280² = 831037742236800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1525 + ... + 6564.

It is an arithmetic number, because the mean of its divisors is an integer number (788775).

Almost surely, 2^20384280 is an apocalyptic number.

20384280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20384280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37861200).

20384280 is an abundant number, since it is smaller than the sum of its proper divisors (55338120).

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

20384280 is a wasteful number, since it uses less digits than its factorization.

20384280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8113 (or 8106 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 20384280 is about 4514.8953476243. The cubic root of 20384280 is about 273.1692385408.

The spelling of 20384280 in words is "twenty million, three hundred eighty-four thousand, two hundred eighty".