687471431257 has 8 divisors (see below), whose sum is σ = 740932720640. Its totient is φ = 634092837840.

The previous prime is 687471431249. The next prime is 687471431279. The reversal of 687471431257 is 752134174786.

It is a happy number.

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 687471431257 - 2³ = 687471431249 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 687471431198 and 687471431207.

It is not an unprimeable number, because it can be changed into a prime (687471431287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20656719 + ... + 20689972.

It is an arithmetic number, because the mean of its divisors is an integer number (92616590080).

Almost surely, 2^687471431257 is an apocalyptic number.

It is an amenable number.

687471431257 is a deficient number, since it is larger than the sum of its proper divisors (53461289383).

687471431257 is a wasteful number, since it uses less digits than its factorization.

687471431257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41347983.

The product of its digits is 7902720, while the sum is 55.

The spelling of 687471431257 in words is "six hundred eighty-seven billion, four hundred seventy-one million, four hundred thirty-one thousand, two hundred fifty-seven".