21049733 has 4 divisors (see below), whose sum is σ = 21074508. Its totient is φ = 21024960.

The previous prime is 21049729. The next prime is 21049759. The reversal of 21049733 is 33794012.

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

It can be written as a sum of positive squares in 2 ways, for example, as 12061729 + 8988004 = 3473^2 + 2998^2 .

It is a cyclic number.

It is not a de Polignac number, because 21049733 - 2² = 21049729 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21049696 and 21049705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21049703) 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, 11066 + ... + 12827.

It is an arithmetic number, because the mean of its divisors is an integer number (5268627).

Almost surely, 2^21049733 is an apocalyptic number.

It is an amenable number.

21049733 is a deficient number, since it is larger than the sum of its proper divisors (24775).

21049733 is an equidigital number, since it uses as much as digits as its factorization.

21049733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24774.

The product of its (nonzero) digits is 4536, while the sum is 29.

The square root of 21049733 is about 4587.9988012204. The cubic root of 21049733 is about 276.1100389133.

The spelling of 21049733 in words is "twenty-one million, forty-nine thousand, seven hundred thirty-three".