21983329 has 4 divisors (see below), whose sum is σ = 23276484. Its totient is φ = 20690176.

The previous prime is 21983327. The next prime is 21983369. The reversal of 21983329 is 92338912.

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

It can be written as a sum of positive squares in 2 ways, for example, as 19184400 + 2798929 = 4380^2 + 1673^2 .

It is a cyclic number.

It is not a de Polignac number, because 21983329 - 2¹ = 21983327 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21983327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 646552 + ... + 646585.

It is an arithmetic number, because the mean of its divisors is an integer number (5819121).

Almost surely, 2^21983329 is an apocalyptic number.

It is an amenable number.

21983329 is a deficient number, since it is larger than the sum of its proper divisors (1293155).

21983329 is a wasteful number, since it uses less digits than its factorization.

21983329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1293154.

The product of its digits is 23328, while the sum is 37.

The square root of 21983329 is about 4688.6382884586. The cubic root of 21983329 is about 280.1331382142.

The spelling of 21983329 in words is "twenty-one million, nine hundred eighty-three thousand, three hundred twenty-nine".