691013836729 has 2 divisors, whose sum is σ = 691013836730. Its totient is φ = 691013836728.

The previous prime is 691013836691. The next prime is 691013836741. The reversal of 691013836729 is 927638310196.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 371508535225 + 319505301504 = 609515^2 + 565248^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-691013836729 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 691013836729.

It is not a weakly prime, because it can be changed into another prime (691013836769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345506918364 + 345506918365.

It is an arithmetic number, because the mean of its divisors is an integer number (345506918365).

Almost surely, 2^691013836729 is an apocalyptic number.

It is an amenable number.

691013836729 is a deficient number, since it is larger than the sum of its proper divisors (1).

691013836729 is an equidigital number, since it uses as much as digits as its factorization.

691013836729 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2939328, while the sum is 55.

The spelling of 691013836729 in words is "six hundred ninety-one billion, thirteen million, eight hundred thirty-six thousand, seven hundred twenty-nine".