21384783 has 16 divisors (see below), whose sum is σ = 36207360. Its totient is φ = 12219768.

The previous prime is 21384773. The next prime is 21384787. The reversal of 21384783 is 38748312.

It is not a de Polignac number, because 21384783 - 2⁴ = 21384767 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21384787) 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 15 ways as a sum of consecutive naturals, for example, 56385 + ... + 56762.

It is an arithmetic number, because the mean of its divisors is an integer number (2262960).

Almost surely, 2^21384783 is an apocalyptic number.

21384783 is a deficient number, since it is larger than the sum of its proper divisors (14822577).

21384783 is a wasteful number, since it uses less digits than its factorization.

21384783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113163 (or 113157 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 21384783 is about 4624.3683893046. The cubic root of 21384783 is about 277.5672882845.

The spelling of 21384783 in words is "twenty-one million, three hundred eighty-four thousand, seven hundred eighty-three".