688707077 has 4 divisors (see below), whose sum is σ = 729219276. Its totient is φ = 648194880.

The previous prime is 688707037. The next prime is 688707091. The reversal of 688707077 is 770707886.

688707077 is an esthetic number in base 14, because in such base its adjacent digits differ by 1.

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

It can be written as a sum of positive squares in 2 ways, for example, as 263770081 + 424936996 = 16241^2 + 20614^2 .

It is a cyclic number.

It is not a de Polignac number, because 688707077 - 2⁶ = 688707013 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 (688707007) 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, 20256074 + ... + 20256107.

It is an arithmetic number, because the mean of its divisors is an integer number (182304819).

Almost surely, 2^688707077 is an apocalyptic number.

It is an amenable number.

688707077 is a deficient number, since it is larger than the sum of its proper divisors (40512199).

688707077 is a wasteful number, since it uses less digits than its factorization.

688707077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40512198.

The product of its (nonzero) digits is 921984, while the sum is 50.

The square root of 688707077 is about 26243.2291648722. The cubic root of 688707077 is about 883.1033154344.

The spelling of 688707077 in words is "six hundred eighty-eight million, seven hundred seven thousand, seventy-seven".