687777407 has 4 divisors (see below), whose sum is σ = 687872640. Its totient is φ = 687682176.

The previous prime is 687777403. The next prime is 687777413. The reversal of 687777407 is 704777786.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 687777407 - 2² = 687777403 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687777403) 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, 35807 + ... + 51552.

It is an arithmetic number, because the mean of its divisors is an integer number (171968160).

Almost surely, 2^687777407 is an apocalyptic number.

687777407 is a deficient number, since it is larger than the sum of its proper divisors (95233).

687777407 is an equidigital number, since it uses as much as digits as its factorization.

687777407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95232.

The product of its (nonzero) digits is 3226944, while the sum is 53.

The square root of 687777407 is about 26225.5106146668. The cubic root of 687777407 is about 882.7057761525.

The spelling of 687777407 in words is "six hundred eighty-seven million, seven hundred seventy-seven thousand, four hundred seven".