20331840 has 56 divisors (see below), whose sum is σ = 64556640. Its totient is φ = 5421568.

The previous prime is 20331803. The next prime is 20331841. The reversal of 20331840 is 4813302.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20331841) 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 in 7 ways as a sum of consecutive naturals, for example, 9630 + ... + 11549.

Almost surely, 2^20331840 is an apocalyptic number.

20331840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20331840 is an abundant number, since it is smaller than the sum of its proper divisors (44224800).

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

20331840 is a wasteful number, since it uses less digits than its factorization.

20331840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21199 (or 21189 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 20331840 is about 4509.0841642178. The cubic root of 20331840 is about 272.9347883259.

The spelling of 20331840 in words is "twenty million, three hundred thirty-one thousand, eight hundred forty".