1687993247 has 8 divisors (see below), whose sum is σ = 1738131360. Its totient is φ = 1638282240.

The previous prime is 1687993201. The next prime is 1687993249. The reversal of 1687993247 is 7423997861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1687993247 - 2⁸ = 1687992991 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1687993192 and 1687993201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1687993249) 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 7 ways as a sum of consecutive naturals, for example, 98747 + ... + 114572.

It is an arithmetic number, because the mean of its divisors is an integer number (217266420).

Almost surely, 2^1687993247 is an apocalyptic number.

1687993247 is a deficient number, since it is larger than the sum of its proper divisors (50138113).

1687993247 is a wasteful number, since it uses less digits than its factorization.

1687993247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213553.

The product of its digits is 4572288, while the sum is 56.

The square root of 1687993247 is about 41085.1949855419. The cubic root of 1687993247 is about 1190.6667748328. Note that the first 3 decimals are identical.

The spelling of 1687993247 in words is "one billion, six hundred eighty-seven million, nine hundred ninety-three thousand, two hundred forty-seven".