21033213 has 8 divisors (see below), whose sum is σ = 28106208. Its totient is φ = 13991184.

The previous prime is 21033203. The next prime is 21033223. The reversal of 21033213 is 31233012.

It is an interprime number because it is at equal distance from previous prime (21033203) and next prime (21033223).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21033213 - 2¹³ = 21025021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21033192 and 21033201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21033203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6106 + ... + 8907.

It is an arithmetic number, because the mean of its divisors is an integer number (3513276).

Almost surely, 2^21033213 is an apocalyptic number.

It is an amenable number.

21033213 is a deficient number, since it is larger than the sum of its proper divisors (7072995).

21033213 is a wasteful number, since it uses less digits than its factorization.

21033213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15483.

The product of its (nonzero) digits is 108, while the sum is 15.

The square root of 21033213 is about 4586.1980986434. The cubic root of 21033213 is about 276.0377888817.

Adding to 21033213 its reverse (31233012), we get a palindrome (52266225).

The spelling of 21033213 in words is "twenty-one million, thirty-three thousand, two hundred thirteen".