21003433 has 8 divisors (see below), whose sum is σ = 23236416. Its totient is φ = 18824400.

The previous prime is 21003431. The next prime is 21003473. The reversal of 21003433 is 33430012.

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

It is a cyclic number.

It is not a de Polignac number, because 21003433 - 2¹ = 21003431 is a prime.

It is a super-2 number, since 2×21003433² = 882288395570978, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21003431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12666 + ... + 14227.

It is an arithmetic number, because the mean of its divisors is an integer number (2904552).

Almost surely, 2^21003433 is an apocalyptic number.

It is an amenable number.

21003433 is a deficient number, since it is larger than the sum of its proper divisors (2232983).

21003433 is a wasteful number, since it uses less digits than its factorization.

21003433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26975.

The product of its (nonzero) digits is 216, while the sum is 16.

The square root of 21003433 is about 4582.9502506573. The cubic root of 21003433 is about 275.9074507661.

Adding to 21003433 its reverse (33430012), we get a palindrome (54433445).

The spelling of 21003433 in words is "twenty-one million, three thousand, four hundred thirty-three".