671803778111 has 4 divisors (see below), whose sum is σ = 687427121832. Its totient is φ = 656180434392.

The previous prime is 671803778071. The next prime is 671803778141. The reversal of 671803778111 is 111877308176.

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 671803778111 - 2⁶ = 671803778047 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 671803778111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671803778141) 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, 7811671796 + ... + 7811671881.

It is an arithmetic number, because the mean of its divisors is an integer number (171856780458).

Almost surely, 2^671803778111 is an apocalyptic number.

671803778111 is a deficient number, since it is larger than the sum of its proper divisors (15623343721).

671803778111 is a wasteful number, since it uses less digits than its factorization.

671803778111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15623343720.

The product of its (nonzero) digits is 395136, while the sum is 50.

The spelling of 671803778111 in words is "six hundred seventy-one billion, eight hundred three million, seven hundred seventy-eight thousand, one hundred eleven".