21943000 has 32 divisors (see below), whose sum is σ = 51348960. Its totient is φ = 8776800.

The previous prime is 21942953. The next prime is 21943001. The reversal of 21943000 is 34912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21943001) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 9972 + ... + 11971.

It is an arithmetic number, because the mean of its divisors is an integer number (1604655).

Almost surely, 2^21943000 is an apocalyptic number.

21943000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21943000 is an abundant number, since it is smaller than the sum of its proper divisors (29405960).

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

21943000 is a wasteful number, since it uses less digits than its factorization.

21943000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21964 (or 21950 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 21943000 is about 4684.3355985668. The cubic root of 21943000 is about 279.9617294633.

Adding to 21943000 its reverse (34912), we get a palindrome (21977912).

The spelling of 21943000 in words is "twenty-one million, nine hundred forty-three thousand".