687405081 has 32 divisors (see below), whose sum is σ = 1061424000. Its totient is φ = 391086080.

The previous prime is 687405079. The next prime is 687405107. The reversal of 687405081 is 180504786.

687405081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 687405081 - 2¹ = 687405079 is a prime.

It is a super-2 number, since 2×687405081² = 945051490769233122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (687405281) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 250525 + ... + 253253.

It is an arithmetic number, because the mean of its divisors is an integer number (33169500).

Almost surely, 2^687405081 is an apocalyptic number.

It is an amenable number.

687405081 is a deficient number, since it is larger than the sum of its proper divisors (374018919).

687405081 is a wasteful number, since it uses less digits than its factorization.

687405081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3209.

The product of its (nonzero) digits is 53760, while the sum is 39.

The square root of 687405081 is about 26218.4111074642. The cubic root of 687405081 is about 882.5464641277.

The spelling of 687405081 in words is "six hundred eighty-seven million, four hundred five thousand, eighty-one".