687743669 has 4 divisors (see below), whose sum is σ = 694420896. Its totient is φ = 681066444.

The previous prime is 687743659. The next prime is 687743689. The reversal of 687743669 is 966347786.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-687743669 is a prime.

It is a super-2 number, since 2×687743669² = 945982708499163122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687743629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3338459 + ... + 3338664.

It is an arithmetic number, because the mean of its divisors is an integer number (173605224).

Almost surely, 2^687743669 is an apocalyptic number.

It is an amenable number.

687743669 is a deficient number, since it is larger than the sum of its proper divisors (6677227).

687743669 is a wasteful number, since it uses less digits than its factorization.

687743669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6677226.

The product of its digits is 9144576, while the sum is 56.

The square root of 687743669 is about 26224.8673781203. The cubic root of 687743669 is about 882.6913425998.

The spelling of 687743669 in words is "six hundred eighty-seven million, seven hundred forty-three thousand, six hundred sixty-nine".