21019233 has 8 divisors (see below), whose sum is σ = 28283200. Its totient is φ = 13884048.

The previous prime is 21019231. The next prime is 21019247. The reversal of 21019233 is 33291012.

It is a happy number.

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

It is not a de Polignac number, because 21019233 - 2¹ = 21019231 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21019231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31813 + ... + 32466.

It is an arithmetic number, because the mean of its divisors is an integer number (3535400).

Almost surely, 2^21019233 is an apocalyptic number.

It is an amenable number.

21019233 is a deficient number, since it is larger than the sum of its proper divisors (7263967).

21019233 is a wasteful number, since it uses less digits than its factorization.

21019233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64391.

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 21019233 is about 4584.6737070374. The cubic root of 21019233 is about 275.9766179520.

The spelling of 21019233 in words is "twenty-one million, nineteen thousand, two hundred thirty-three".