678751221193 has 4 divisors (see below), whose sum is σ = 678755708548. Its totient is φ = 678746733840.

The previous prime is 678751221179. The next prime is 678751221223. The reversal of 678751221193 is 391122157876.

678751221193 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 415339003024 + 263412218169 = 644468^2 + 513237^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678751221193 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 678751221193.

It is not an unprimeable number, because it can be changed into a prime (678751221133) 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, 2008578 + ... + 2322043.

It is an arithmetic number, because the mean of its divisors is an integer number (169688927137).

Almost surely, 2^678751221193 is an apocalyptic number.

It is an amenable number.

678751221193 is a deficient number, since it is larger than the sum of its proper divisors (4487355).

678751221193 is a wasteful number, since it uses less digits than its factorization.

678751221193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4487354.

The product of its digits is 1270080, while the sum is 52.

The spelling of 678751221193 in words is "six hundred seventy-eight billion, seven hundred fifty-one million, two hundred twenty-one thousand, one hundred ninety-three".