20766223 has 4 divisors (see below), whose sum is σ = 20783200. Its totient is φ = 20749248.

The previous prime is 20766211. The next prime is 20766241. The reversal of 20766223 is 32266702.

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

It is a cyclic number.

It is not a de Polignac number, because 20766223 - 2²¹ = 18669071 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20766191 and 20766200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20766203) 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, 6498 + ... + 9151.

It is an arithmetic number, because the mean of its divisors is an integer number (5195800).

Almost surely, 2^20766223 is an apocalyptic number.

20766223 is a deficient number, since it is larger than the sum of its proper divisors (16977).

20766223 is a wasteful number, since it uses less digits than its factorization.

20766223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16976.

The product of its (nonzero) digits is 6048, while the sum is 28.

The square root of 20766223 is about 4556.9971472451. The cubic root of 20766223 is about 274.8648283353.

It can be divided in two parts, 207 and 66223, that added together give a triangular number (66430 = T₃₆₄).

The spelling of 20766223 in words is "twenty million, seven hundred sixty-six thousand, two hundred twenty-three".