687555431 has 2 divisors, whose sum is σ = 687555432. Its totient is φ = 687555430.

The previous prime is 687555383. The next prime is 687555437. The reversal of 687555431 is 134555786.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 687555431 - 2¹⁰ = 687554407 is a prime.

It is a super-2 number, since 2×687555431² = 945464941395191522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687555437) 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 as a sum of consecutive naturals, namely, 343777715 + 343777716.

It is an arithmetic number, because the mean of its divisors is an integer number (343777716).

Almost surely, 2^687555431 is an apocalyptic number.

687555431 is a deficient number, since it is larger than the sum of its proper divisors (1).

687555431 is an equidigital number, since it uses as much as digits as its factorization.

687555431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 504000, while the sum is 44.

The square root of 687555431 is about 26221.2782106441. The cubic root of 687555431 is about 882.6108032836.

The spelling of 687555431 in words is "six hundred eighty-seven million, five hundred fifty-five thousand, four hundred thirty-one".