21847983 has 4 divisors (see below), whose sum is σ = 29130648. Its totient is φ = 14565320.

The previous prime is 21847961. The next prime is 21847993. The reversal of 21847983 is 38974812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21847983 - 2⁹ = 21847471 is a prime.

It is a super-2 number, since 2×21847983² = 954668722336578, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21847993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3641328 + ... + 3641333.

It is an arithmetic number, because the mean of its divisors is an integer number (7282662).

Almost surely, 2^21847983 is an apocalyptic number.

21847983 is a deficient number, since it is larger than the sum of its proper divisors (7282665).

21847983 is an equidigital number, since it uses as much as digits as its factorization.

21847983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7282664.

The product of its digits is 96768, while the sum is 42.

The square root of 21847983 is about 4674.1826023381. The cubic root of 21847983 is about 279.5570504903.

The spelling of 21847983 in words is "twenty-one million, eight hundred forty-seven thousand, nine hundred eighty-three".