21340283 has 4 divisors (see below), whose sum is σ = 21354480. Its totient is φ = 21326088.

The previous prime is 21340279. The next prime is 21340289. The reversal of 21340283 is 38204312.

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 21340283 - 2² = 21340279 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21340289) 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, 4535 + ... + 7952.

It is an arithmetic number, because the mean of its divisors is an integer number (5338620).

Almost surely, 2^21340283 is an apocalyptic number.

21340283 is a deficient number, since it is larger than the sum of its proper divisors (14197).

21340283 is a wasteful number, since it uses less digits than its factorization.

21340283 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14196.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 21340283 is about 4619.5544157418. The cubic root of 21340283 is about 277.3746229064.

Adding to 21340283 its reverse (38204312), we get a palindrome (59544595).

The spelling of 21340283 in words is "twenty-one million, three hundred forty thousand, two hundred eighty-three".