21319983 has 16 divisors (see below), whose sum is σ = 31699200. Its totient is φ = 14162040.

The previous prime is 21319981. The next prime is 21319997. The reversal of 21319983 is 38991312.

It is not a de Polignac number, because 21319983 - 2¹ = 21319981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21319981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7128 + ... + 9666.

It is an arithmetic number, because the mean of its divisors is an integer number (1981200).

Almost surely, 2^21319983 is an apocalyptic number.

21319983 is a deficient number, since it is larger than the sum of its proper divisors (10379217).

21319983 is a wasteful number, since it uses less digits than its factorization.

21319983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2859 (or 2853 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 21319983 is about 4617.3567113664. The cubic root of 21319983 is about 277.2866438920.

The spelling of 21319983 in words is "twenty-one million, three hundred nineteen thousand, nine hundred eighty-three".