21183730 has 16 divisors (see below), whose sum is σ = 38237184. Its totient is φ = 8449840.

The previous prime is 21183719. The next prime is 21183737. The reversal of 21183730 is 3738112.

It is a junction number, because it is equal to n+sod(n) for n = 21183695 and 21183704.

It is not an unprimeable number, because it can be changed into a prime (21183737) 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, 1065 + ... + 6595.

It is an arithmetic number, because the mean of its divisors is an integer number (2389824).

Almost surely, 2^21183730 is an apocalyptic number.

21183730 is a deficient number, since it is larger than the sum of its proper divisors (17053454).

21183730 is a wasteful number, since it uses less digits than its factorization.

21183730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5921.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 21183730 is about 4602.5786250753. The cubic root of 21183730 is about 276.6946811200.

The spelling of 21183730 in words is "twenty-one million, one hundred eighty-three thousand, seven hundred thirty".