21840010 has 8 divisors (see below), whose sum is σ = 39312036. Its totient is φ = 8736000.

The previous prime is 21839989. The next prime is 21840023. The reversal of 21840010 is 1004812.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19562929 + 2277081 = 4423^2 + 1509^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1091991 + ... + 1092010.

Almost surely, 2^21840010 is an apocalyptic number.

21840010 is a deficient number, since it is larger than the sum of its proper divisors (17472026).

21840010 is a wasteful number, since it uses less digits than its factorization.

21840010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2184008.

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

The square root of 21840010 is about 4673.3296481203. The cubic root of 21840010 is about 279.5230400350.

Adding to 21840010 its reverse (1004812), we get a palindrome (22844822).

The spelling of 21840010 in words is "twenty-one million, eight hundred forty thousand, ten".