20688928271 has 4 divisors (see below), whose sum is σ = 22569739944. Its totient is φ = 18808116600.

The previous prime is 20688928189. The next prime is 20688928289. The reversal of 20688928271 is 17282988602.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20688928271 - 2¹⁰ = 20688927247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20688922271) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 940405820 + ... + 940405841.

It is an arithmetic number, because the mean of its divisors is an integer number (5642434986).

Almost surely, 2^20688928271 is an apocalyptic number.

20688928271 is a deficient number, since it is larger than the sum of its proper divisors (1880811673).

20688928271 is a wasteful number, since it uses less digits than its factorization.

20688928271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1880811672.

The product of its (nonzero) digits is 1548288, while the sum is 53.

The spelling of 20688928271 in words is "twenty billion, six hundred eighty-eight million, nine hundred twenty-eight thousand, two hundred seventy-one".