20640076 has 12 divisors (see below), whose sum is σ = 36363600. Its totient is φ = 10250480.

The previous prime is 20640073. The next prime is 20640089. The reversal of 20640076 is 67004602.

It is a self number, because there is not a number n which added to its sum of digits gives 20640076.

It is not an unprimeable number, because it can be changed into a prime (20640071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16720 + ... + 17911.

It is an arithmetic number, because the mean of its divisors is an integer number (3030300).

Almost surely, 2^20640076 is an apocalyptic number.

It is an amenable number.

20640076 is a deficient number, since it is larger than the sum of its proper divisors (15723524).

20640076 is a wasteful number, since it uses less digits than its factorization.

20640076 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34784 (or 34782 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 20640076 is about 4543.1350409161. The cubic root of 20640076 is about 274.3071306959.

Adding to 20640076 its reverse (67004602), we get a palindrome (87644678).

The spelling of 20640076 in words is "twenty million, six hundred forty thousand, seventy-six".