20768666 has 4 divisors (see below), whose sum is σ = 31153002. Its totient is φ = 10384332.

The previous prime is 20768617. The next prime is 20768711. The reversal of 20768666 is 66686702.

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

It can be written as a sum of positive squares in only one way, i.e., 14984641 + 5784025 = 3871^2 + 2405^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5192165 + ... + 5192168.

Almost surely, 2^20768666 is an apocalyptic number.

20768666 is a deficient number, since it is larger than the sum of its proper divisors (10384336).

20768666 is a wasteful number, since it uses less digits than its factorization.

20768666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10384335.

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 20768666 is about 4557.2651886850. The cubic root of 20768666 is about 274.8756065503.

The spelling of 20768666 in words is "twenty million, seven hundred sixty-eight thousand, six hundred sixty-six".