678727631551 has 4 divisors (see below), whose sum is σ = 685070880552. Its totient is φ = 672384382552.

The previous prime is 678727631473. The next prime is 678727631567. The reversal of 678727631551 is 155136727876.

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 678727631551 - 2¹³ = 678727623359 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678727661551) 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, 3171624340 + ... + 3171624553.

It is an arithmetic number, because the mean of its divisors is an integer number (171267720138).

Almost surely, 2^678727631551 is an apocalyptic number.

678727631551 is a deficient number, since it is larger than the sum of its proper divisors (6343249001).

678727631551 is a wasteful number, since it uses less digits than its factorization.

678727631551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6343249000.

The product of its digits is 14817600, while the sum is 58.

The spelling of 678727631551 in words is "six hundred seventy-eight billion, seven hundred twenty-seven million, six hundred thirty-one thousand, five hundred fifty-one".