687445765551 has 6 divisors (see below), whose sum is σ = 992977216920. Its totient is φ = 458297177028.

The previous prime is 687445765547. The next prime is 687445765607. The reversal of 687445765551 is 155567544786.

It is a happy number.

687445765551 is a `hidden beast` number, since 6 + 8 + 7 + 4 + 4 + 5 + 76 + 5 + 551 = 666.

It is not a de Polignac number, because 687445765551 - 2² = 687445765547 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687445761551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38191431411 + ... + 38191431428.

It is an arithmetic number, because the mean of its divisors is an integer number (165496202820).

Almost surely, 2^687445765551 is an apocalyptic number.

687445765551 is a deficient number, since it is larger than the sum of its proper divisors (305531451369).

687445765551 is a wasteful number, since it uses less digits than its factorization.

687445765551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76382862845 (or 76382862842 counting only the distinct ones).

The product of its digits is 141120000, while the sum is 63.

The spelling of 687445765551 in words is "six hundred eighty-seven billion, four hundred forty-five million, seven hundred sixty-five thousand, five hundred fifty-one".