688404737 has 2 divisors, whose sum is σ = 688404738. Its totient is φ = 688404736.

The previous prime is 688404677. The next prime is 688404763. The reversal of 688404737 is 737404886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 655411201 + 32993536 = 25601^2 + 5744^2 .

It is a cyclic number.

It is not a de Polignac number, because 688404737 - 2¹⁰ = 688403713 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 688404691 and 688404700.

It is not a weakly prime, because it can be changed into another prime (688404767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344202368 + 344202369.

It is an arithmetic number, because the mean of its divisors is an integer number (344202369).

Almost surely, 2^688404737 is an apocalyptic number.

It is an amenable number.

688404737 is a deficient number, since it is larger than the sum of its proper divisors (1).

688404737 is an equidigital number, since it uses as much as digits as its factorization.

688404737 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 903168, while the sum is 47.

The square root of 688404737 is about 26237.4681895948. The cubic root of 688404737 is about 882.9740700967.

The spelling of 688404737 in words is "six hundred eighty-eight million, four hundred four thousand, seven hundred thirty-seven".