691473229 has 2 divisors, whose sum is σ = 691473230. Its totient is φ = 691473228.

The previous prime is 691473227. The next prime is 691473253. The reversal of 691473229 is 922374196.

691473229 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 653058025 + 38415204 = 25555^2 + 6198^2 .

It is a cyclic number.

It is not a de Polignac number, because 691473229 - 2¹ = 691473227 is a prime.

Together with 691473227, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (691473227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345736614 + 345736615.

It is an arithmetic number, because the mean of its divisors is an integer number (345736615).

Almost surely, 2^691473229 is an apocalyptic number.

It is an amenable number.

691473229 is a deficient number, since it is larger than the sum of its proper divisors (1).

691473229 is an equidigital number, since it uses as much as digits as its factorization.

691473229 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 43.

The square root of 691473229 is about 26295.8785553934. The cubic root of 691473229 is about 884.2840471318.

The spelling of 691473229 in words is "six hundred ninety-one million, four hundred seventy-three thousand, two hundred twenty-nine".