20840686177 has 8 divisors (see below), whose sum is σ = 21045982464. Its totient is φ = 20635447008.

The previous prime is 20840686151. The next prime is 20840686187. The reversal of 20840686177 is 77168604802.

It is a happy number.

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 20840686177 - 2¹⁹ = 20840161889 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20840686177.

It is not an unprimeable number, because it can be changed into a prime (20840686187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1425768 + ... + 1440310.

It is an arithmetic number, because the mean of its divisors is an integer number (2630747808).

Almost surely, 2^20840686177 is an apocalyptic number.

It is an amenable number.

20840686177 is a deficient number, since it is larger than the sum of its proper divisors (205296287).

20840686177 is a wasteful number, since it uses less digits than its factorization.

20840686177 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28559.

The product of its (nonzero) digits is 903168, while the sum is 49.

The spelling of 20840686177 in words is "twenty billion, eight hundred forty million, six hundred eighty-six thousand, one hundred seventy-seven".