20660571 has 6 divisors (see below), whose sum is σ = 29843060. Its totient is φ = 13773708.

The previous prime is 20660567. The next prime is 20660579. The reversal of 20660571 is 17506602.

It is not a de Polignac number, because 20660571 - 2² = 20660567 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20660579) 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, 1147801 + ... + 1147818.

Almost surely, 2^20660571 is an apocalyptic number.

20660571 is a deficient number, since it is larger than the sum of its proper divisors (9182489).

20660571 is a wasteful number, since it uses less digits than its factorization.

20660571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2295625 (or 2295622 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 20660571 is about 4545.3900822702. The cubic root of 20660571 is about 274.3978936832.

The spelling of 20660571 in words is "twenty million, six hundred sixty thousand, five hundred seventy-one".