20170617806 has 4 divisors (see below), whose sum is σ = 30255926712. Its totient is φ = 10085308902.

The previous prime is 20170617791. The next prime is 20170617811. The reversal of 20170617806 is 60871607102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60871607102 = 2 ⋅30435803551.

It is a self number, because there is not a number n which added to its sum of digits gives 20170617806.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5042654450 + ... + 5042654453.

It is an arithmetic number, because the mean of its divisors is an integer number (7563981678).

Almost surely, 2^20170617806 is an apocalyptic number.

20170617806 is a deficient number, since it is larger than the sum of its proper divisors (10085308906).

20170617806 is a wasteful number, since it uses less digits than its factorization.

20170617806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10085308905.

The product of its (nonzero) digits is 28224, while the sum is 38.

The spelling of 20170617806 in words is "twenty billion, one hundred seventy million, six hundred seventeen thousand, eight hundred six".