20868784 has 10 divisors (see below), whose sum is σ = 40433300. Its totient is φ = 10434384.

The previous prime is 20868769. The next prime is 20868823. The reversal of 20868784 is 48786802.

It is a super-2 number, since 2×20868784² = 871012291277312, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20868784.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 652134 + ... + 652165.

It is an arithmetic number, because the mean of its divisors is an integer number (4043330).

Almost surely, 2^20868784 is an apocalyptic number.

It is an amenable number.

20868784 is a deficient number, since it is larger than the sum of its proper divisors (19564516).

20868784 is a wasteful number, since it uses less digits than its factorization.

20868784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1304307 (or 1304301 counting only the distinct ones).

The product of its (nonzero) digits is 172032, while the sum is 43.

The square root of 20868784 is about 4568.2364212024. The cubic root of 20868784 is about 275.3165896610.

The spelling of 20868784 in words is "twenty million, eight hundred sixty-eight thousand, seven hundred eighty-four".