21733920 has 288 divisors, whose sum is σ = 84756672. Its totient is φ = 5225472.

The previous prime is 21733913. The next prime is 21733969. The reversal of 21733920 is 2933712.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 505419 + ... + 505461.

It is an arithmetic number, because the mean of its divisors is an integer number (294294).

Almost surely, 2^21733920 is an apocalyptic number.

21733920 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 21733920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42378336).

21733920 is an abundant number, since it is smaller than the sum of its proper divisors (63022752).

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

21733920 is a wasteful number, since it uses less digits than its factorization.

21733920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86 (or 66 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 27.

The square root of 21733920 is about 4661.9652508357. The cubic root of 21733920 is about 279.0697016279.

The spelling of 21733920 in words is "twenty-one million, seven hundred thirty-three thousand, nine hundred twenty".