21383810 has 16 divisors (see below), whose sum is σ = 43989696. Its totient is φ = 7331568.

The previous prime is 21383777. The next prime is 21383833. The reversal of 21383810 is 1838312.

It is a super-2 number, since 2×21383810² = 914534660232200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21383810.

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, 152672 + ... + 152811.

It is an arithmetic number, because the mean of its divisors is an integer number (2749356).

Almost surely, 2^21383810 is an apocalyptic number.

21383810 is an abundant number, since it is smaller than the sum of its proper divisors (22605886).

21383810 is a wasteful number, since it uses less digits than its factorization.

21383810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 305497.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 21383810 is about 4624.2631845517. The cubic root of 21383810 is about 277.5630784831.

The spelling of 21383810 in words is "twenty-one million, three hundred eighty-three thousand, eight hundred ten".