21888983 has 4 divisors (see below), whose sum is σ = 21898968. Its totient is φ = 21879000.

The previous prime is 21888973. The next prime is 21888989. The reversal of 21888983 is 38988812.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21888983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21888989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116 + ... + 6617.

It is an arithmetic number, because the mean of its divisors is an integer number (5474742).

Almost surely, 2^21888983 is an apocalyptic number.

21888983 is a deficient number, since it is larger than the sum of its proper divisors (9985).

21888983 is an equidigital number, since it uses as much as digits as its factorization.

21888983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9984.

The product of its digits is 221184, while the sum is 47.

The square root of 21888983 is about 4678.5663402371. The cubic root of 21888983 is about 279.7318137894.

The spelling of 21888983 in words is "twenty-one million, eight hundred eighty-eight thousand, nine hundred eighty-three".