20818733 has 4 divisors (see below), whose sum is σ = 22420188. Its totient is φ = 19217280.

The previous prime is 20818649. The next prime is 20818739. The reversal of 20818733 is 33781802.

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 2815684 + 18003049 = 1678^2 + 4243^2 .

It is a cyclic number.

It is not a de Polignac number, because 20818733 - 2⁸ = 20818477 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20818733.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20818739) 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, 800708 + ... + 800733.

It is an arithmetic number, because the mean of its divisors is an integer number (5605047).

Almost surely, 2^20818733 is an apocalyptic number.

It is an amenable number.

20818733 is a deficient number, since it is larger than the sum of its proper divisors (1601455).

20818733 is a wasteful number, since it uses less digits than its factorization.

20818733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1601454.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 20818733 is about 4562.7549791765. The cubic root of 20818733 is about 275.0963100682.

The spelling of 20818733 in words is "twenty million, eight hundred eighteen thousand, seven hundred thirty-three".