688091429 has 2 divisors, whose sum is σ = 688091430. Its totient is φ = 688091428.

The previous prime is 688091423. The next prime is 688091449. The reversal of 688091429 is 924190886.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 685235329 + 2856100 = 26177^2 + 1690^2 .

It is a cyclic number.

It is not a de Polignac number, because 688091429 - 2⁴ = 688091413 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (688091423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344045714 + 344045715.

It is an arithmetic number, because the mean of its divisors is an integer number (344045715).

Almost surely, 2^688091429 is an apocalyptic number.

It is an amenable number.

688091429 is a deficient number, since it is larger than the sum of its proper divisors (1).

688091429 is an equidigital number, since it uses as much as digits as its factorization.

688091429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 47.

The square root of 688091429 is about 26231.4968882830. The cubic root of 688091429 is about 882.8400961884.

The spelling of 688091429 in words is "six hundred eighty-eight million, ninety-one thousand, four hundred twenty-nine".