20929768 has 8 divisors (see below), whose sum is σ = 39243330. Its totient is φ = 10464880.

The previous prime is 20929759. The next prime is 20929789. The reversal of 20929768 is 86792902.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 15350724 + 5579044 = 3918^2 + 2362^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1308103 + ... + 1308118.

Almost surely, 2^20929768 is an apocalyptic number.

It is an amenable number.

20929768 is a deficient number, since it is larger than the sum of its proper divisors (18313562).

20929768 is a wasteful number, since it uses less digits than its factorization.

20929768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2616227 (or 2616223 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 20929768 is about 4574.9063378391. The cubic root of 20929768 is about 275.5845110147.

The spelling of 20929768 in words is "twenty million, nine hundred twenty-nine thousand, seven hundred sixty-eight".