20666600 has 24 divisors (see below), whose sum is σ = 48050310. Its totient is φ = 8266560.

The previous prime is 20666599. The next prime is 20666603. The reversal of 20666600 is 666602.

20666600 = T₁₀₀ + T₁₀₁ + ... + T₄₉₉.

It can be written as a sum of positive squares in 3 ways, for example, as 18992164 + 1674436 = 4358^2 + 1294^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20666600.

It is not an unprimeable number, because it can be changed into a prime (20666603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 51467 + ... + 51866.

Almost surely, 2^20666600 is an apocalyptic number.

20666600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20666600 is an abundant number, since it is smaller than the sum of its proper divisors (27383710).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20666600 is a wasteful number, since it uses less digits than its factorization.

20666600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103349 (or 103340 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 20666600 is about 4546.0532333003. The cubic root of 20666600 is about 274.4245819421.

The spelling of 20666600 in words is "twenty million, six hundred sixty-six thousand, six hundred".