20660871 has 48 divisors (see below), whose sum is σ = 35546112. Its totient is φ = 10443840.

The previous prime is 20660869. The next prime is 20660879. The reversal of 20660871 is 17806602.

It is a happy number.

It is not a de Polignac number, because 20660871 - 2¹ = 20660869 is a prime.

It is a super-3 number, since 3×20660871³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20660879) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 119341 + ... + 119513.

It is an arithmetic number, because the mean of its divisors is an integer number (740544).

Almost surely, 2^20660871 is an apocalyptic number.

20660871 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20660871 is a deficient number, since it is larger than the sum of its proper divisors (14885241).

20660871 is a wasteful number, since it uses less digits than its factorization.

20660871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252 (or 241 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 20660871 is about 4545.4230826184. The cubic root of 20660871 is about 274.3992218002.

The spelling of 20660871 in words is "twenty million, six hundred sixty thousand, eight hundred seventy-one".