671803378567 has 4 divisors (see below), whose sum is σ = 671805062656. Its totient is φ = 671801694480.

The previous prime is 671803378559. The next prime is 671803378579. The reversal of 671803378567 is 765873308176.

It is a happy number.

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 671803378567 - 2³ = 671803378559 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 (671803372567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131578 + ... + 1166584.

It is an arithmetic number, because the mean of its divisors is an integer number (167951265664).

Almost surely, 2^671803378567 is an apocalyptic number.

671803378567 is a deficient number, since it is larger than the sum of its proper divisors (1684089).

671803378567 is a wasteful number, since it uses less digits than its factorization.

671803378567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1684088.

The product of its (nonzero) digits is 35562240, while the sum is 61.

The spelling of 671803378567 in words is "six hundred seventy-one billion, eight hundred three million, three hundred seventy-eight thousand, five hundred sixty-seven".