688342787 has 4 divisors (see below), whose sum is σ = 750919416. Its totient is φ = 625766160.

The previous prime is 688342763. The next prime is 688342829. The reversal of 688342787 is 787243886.

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 688342787 - 2⁶ = 688342723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688342387) 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, 31288298 + ... + 31288319.

It is an arithmetic number, because the mean of its divisors is an integer number (187729854).

Almost surely, 2^688342787 is an apocalyptic number.

688342787 is a deficient number, since it is larger than the sum of its proper divisors (62576629).

688342787 is a wasteful number, since it uses less digits than its factorization.

688342787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62576628.

The product of its digits is 3612672, while the sum is 53.

The square root of 688342787 is about 26236.2875994299. The cubic root of 688342787 is about 882.9475828276.

The spelling of 688342787 in words is "six hundred eighty-eight million, three hundred forty-two thousand, seven hundred eighty-seven".