21983340 has 96 divisors (see below), whose sum is σ = 65028096. Its totient is φ = 5541120.

The previous prime is 21983327. The next prime is 21983369. The reversal of 21983340 is 4338912.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 21983298 and 21983307.

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 31 ways as a sum of consecutive naturals, for example, 98469 + ... + 98691.

It is an arithmetic number, because the mean of its divisors is an integer number (677376).

Almost surely, 2^21983340 is an apocalyptic number.

21983340 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 21983340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32514048).

21983340 is an abundant number, since it is smaller than the sum of its proper divisors (43044756).

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

21983340 is a wasteful number, since it uses less digits than its factorization.

21983340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319 (or 317 counting only the distinct ones).

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

The square root of 21983340 is about 4688.6394615069. The cubic root of 21983340 is about 280.1331849385.

The spelling of 21983340 in words is "twenty-one million, nine hundred eighty-three thousand, three hundred forty".