20660385 has 8 divisors (see below), whose sum is σ = 33056640. Its totient is φ = 11018864.

The previous prime is 20660377. The next prime is 20660399. The reversal of 20660385 is 58306602.

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 20660385 - 2³ = 20660377 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 688665 + ... + 688694.

It is an arithmetic number, because the mean of its divisors is an integer number (4132080).

Almost surely, 2^20660385 is an apocalyptic number.

It is an amenable number.

20660385 is a deficient number, since it is larger than the sum of its proper divisors (12396255).

20660385 is a wasteful number, since it uses less digits than its factorization.

20660385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377367.

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 20660385 is about 4545.3696219340. The cubic root of 20660385 is about 274.3970702441.

Adding to 20660385 its reverse (58306602), we get a palindrome (78966987).

The spelling of 20660385 in words is "twenty million, six hundred sixty thousand, three hundred eighty-five".