21841000 has 32 divisors (see below), whose sum is σ = 51110280. Its totient is φ = 8736000.

The previous prime is 21840997. The next prime is 21841021. The reversal of 21841000 is 14812.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 736164 + 21104836 = 858^2 + 4594^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9921 + ... + 11920.

Almost surely, 2^21841000 is an apocalyptic number.

21841000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21841000 is an abundant number, since it is smaller than the sum of its proper divisors (29269280).

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

21841000 is a wasteful number, since it uses less digits than its factorization.

21841000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21862 (or 21848 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 21841000 is about 4673.4355671176. The cubic root of 21841000 is about 279.5272635316.

Adding to 21841000 its reverse (14812), we get a palindrome (21855812).

The spelling of 21841000 in words is "twenty-one million, eight hundred forty-one thousand".