21330047 has 2 divisors, whose sum is σ = 21330048. Its totient is φ = 21330046.

The previous prime is 21329999. The next prime is 21330059. The reversal of 21330047 is 74003312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21330047 - 2⁶ = 21329983 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21330097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10665023 + 10665024.

It is an arithmetic number, because the mean of its divisors is an integer number (10665024).

Almost surely, 2^21330047 is an apocalyptic number.

21330047 is a deficient number, since it is larger than the sum of its proper divisors (1).

21330047 is an equidigital number, since it uses as much as digits as its factorization.

21330047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 21330047 is about 4618.4463837962. The cubic root of 21330047 is about 277.3302676572.

Adding to 21330047 its reverse (74003312), we get a palindrome (95333359).

The spelling of 21330047 in words is "twenty-one million, three hundred thirty thousand, forty-seven".