20669943 has 16 divisors (see below), whose sum is σ = 33350400. Its totient is φ = 11116416.

The previous prime is 20669941. The next prime is 20670007. The reversal of 20669943 is 34996602.

It is a happy number.

It is not a de Polignac number, because 20669943 - 2¹ = 20669941 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20669941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28593 + ... + 29306.

It is an arithmetic number, because the mean of its divisors is an integer number (2084400).

Almost surely, 2^20669943 is an apocalyptic number.

20669943 is a deficient number, since it is larger than the sum of its proper divisors (12680457).

20669943 is a wasteful number, since it uses less digits than its factorization.

20669943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57926.

The product of its (nonzero) digits is 69984, while the sum is 39.

The square root of 20669943 is about 4546.4209000047. The cubic root of 20669943 is about 274.4393779885.

It can be divided in two parts, 20669 and 943, that added together give a palindrome (21612).

The spelling of 20669943 in words is "twenty million, six hundred sixty-nine thousand, nine hundred forty-three".