21283347 has 4 divisors (see below), whose sum is σ = 28377800. Its totient is φ = 14188896.

The previous prime is 21283333. The next prime is 21283351. The reversal of 21283347 is 74338212.

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

It is not a de Polignac number, because 21283347 - 2⁴ = 21283331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21283307) 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, 3547222 + ... + 3547227.

It is an arithmetic number, because the mean of its divisors is an integer number (7094450).

Almost surely, 2^21283347 is an apocalyptic number.

21283347 is a deficient number, since it is larger than the sum of its proper divisors (7094453).

21283347 is an equidigital number, since it uses as much as digits as its factorization.

21283347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7094452.

The product of its digits is 8064, while the sum is 30.

The square root of 21283347 is about 4613.3878007382. The cubic root of 21283347 is about 277.1277241609.

The spelling of 21283347 in words is "twenty-one million, two hundred eighty-three thousand, three hundred forty-seven".