20666633 has 8 divisors (see below), whose sum is σ = 22374408. Its totient is φ = 18975744.

The previous prime is 20666621. The next prime is 20666651. The reversal of 20666633 is 33666602.

It can be written as a sum of positive squares in 4 ways, for example, as 344569 + 20322064 = 587^2 + 4508^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20666633 - 2⁸ = 20666377 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20666633.

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

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1610 + ... + 6627.

It is an arithmetic number, because the mean of its divisors is an integer number (2796801).

Almost surely, 2^20666633 is an apocalyptic number.

It is an amenable number.

20666633 is a deficient number, since it is larger than the sum of its proper divisors (1707775).

20666633 is a wasteful number, since it uses less digits than its factorization.

20666633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8443.

The product of its (nonzero) digits is 23328, while the sum is 32.

The square root of 20666633 is about 4546.0568628208. The cubic root of 20666633 is about 274.4247280072.

The spelling of 20666633 in words is "twenty million, six hundred sixty-six thousand, six hundred thirty-three".