687660786 has 32 divisors (see below), whose sum is σ = 1577433600. Its totient is φ = 221825520.

The previous prime is 687660767. The next prime is 687660889. The reversal of 687660786 is 687066786.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 203721 + ... + 207068.

It is an arithmetic number, because the mean of its divisors is an integer number (49294800).

Almost surely, 2^687660786 is an apocalyptic number.

687660786 is an abundant number, since it is smaller than the sum of its proper divisors (889772814).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

687660786 is a wasteful number, since it uses less digits than its factorization.

687660786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410831 (or 410825 counting only the distinct ones).

The product of its (nonzero) digits is 4064256, while the sum is 54.

The square root of 687660786 is about 26223.2870937264. The cubic root of 687660786 is about 882.6558821761.

The spelling of 687660786 in words is "six hundred eighty-seven million, six hundred sixty thousand, seven hundred eighty-six".