687429081 has 6 divisors (see below), whose sum is σ = 992953130. Its totient is φ = 458286048.

The previous prime is 687429073. The next prime is 687429091. The reversal of 687429081 is 180924786.

It can be written as a sum of positive squares in only one way, i.e., 428862681 + 258566400 = 20709^2 + 16080^2 .

It is not a de Polignac number, because 687429081 - 2³ = 687429073 is a prime.

It is a super-2 number, since 2×687429081² = 945117482809009122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687429091) 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 5 ways as a sum of consecutive naturals, for example, 38190496 + ... + 38190513.

Almost surely, 2^687429081 is an apocalyptic number.

It is an amenable number.

687429081 is a deficient number, since it is larger than the sum of its proper divisors (305524049).

687429081 is a wasteful number, since it uses less digits than its factorization.

687429081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76381015 (or 76381012 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 687429081 is about 26218.8687971087. The cubic root of 687429081 is about 882.5567350578.

The spelling of 687429081 in words is "six hundred eighty-seven million, four hundred twenty-nine thousand, eighty-one".