20868149871 has 12 divisors (see below), whose sum is σ = 30151895280. Its totient is φ = 13907940480.

The previous prime is 20868149833. The next prime is 20868149879. The reversal of 20868149871 is 17894186802.

20868149871 is a `hidden beast` number, since 2 + 0 + 8 + 6 + 81 + 498 + 71 = 666.

It is not a de Polignac number, because 20868149871 - 2⁶ = 20868149807 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20868149879) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 314691 + ... + 375188.

It is an arithmetic number, because the mean of its divisors is an integer number (2512657940).

Almost surely, 2^20868149871 is an apocalyptic number.

20868149871 is a deficient number, since it is larger than the sum of its proper divisors (9283745409).

20868149871 is a wasteful number, since it uses less digits than its factorization.

20868149871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693246 (or 693243 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 54.

The spelling of 20868149871 in words is "twenty billion, eight hundred sixty-eight million, one hundred forty-nine thousand, eight hundred seventy-one".