20606666 has 12 divisors (see below), whose sum is σ = 32314002. Its totient is φ = 9854856.

The previous prime is 20606627. The next prime is 20606681. The reversal of 20606666 is 66660602.

It can be written as a sum of positive squares in only one way, i.e., 15832441 + 4774225 = 3979^2 + 2185^2 .

20606666 is a modest number, since divided by 6666 gives 2060 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8681 + ... + 10796.

Almost surely, 2^20606666 is an apocalyptic number.

20606666 is a deficient number, since it is larger than the sum of its proper divisors (11707336).

20606666 is a wasteful number, since it uses less digits than its factorization.

20606666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19525 (or 19502 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 32.

The square root of 20606666 is about 4539.4565754064. The cubic root of 20606666 is about 274.1590441839.

The spelling of 20606666 in words is "twenty million, six hundred six thousand, six hundred sixty-six".