20536666 has 8 divisors (see below), whose sum is σ = 30873780. Its totient is φ = 10245408.

The previous prime is 20536643. The next prime is 20536667. The reversal of 20536666 is 66663502.

It can be written as a sum of positive squares in 2 ways, for example, as 18241441 + 2295225 = 4271^2 + 1515^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (20536667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10321 + ... + 12148.

Almost surely, 2^20536666 is an apocalyptic number.

20536666 is a deficient number, since it is larger than the sum of its proper divisors (10337114).

20536666 is a wasteful number, since it uses less digits than its factorization.

20536666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22928.

The product of its (nonzero) digits is 38880, while the sum is 34.

The square root of 20536666 is about 4531.7398424888. The cubic root of 20536666 is about 273.8482563269.

The spelling of 20536666 in words is "twenty million, five hundred thirty-six thousand, six hundred sixty-six".