689435491 has 2 divisors, whose sum is σ = 689435492. Its totient is φ = 689435490.

The previous prime is 689435471. The next prime is 689435519. The reversal of 689435491 is 194534986.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 689435491 - 2⁹ = 689434979 is a prime.

It is a super-2 number, since 2×689435491² = 950642592500822162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (689435471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344717745 + 344717746.

It is an arithmetic number, because the mean of its divisors is an integer number (344717746).

Almost surely, 2^689435491 is an apocalyptic number.

689435491 is a deficient number, since it is larger than the sum of its proper divisors (1).

689435491 is an equidigital number, since it uses as much as digits as its factorization.

689435491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 933120, while the sum is 49.

The square root of 689435491 is about 26257.1036293038. The cubic root of 689435491 is about 883.4145450748.

The spelling of 689435491 in words is "six hundred eighty-nine million, four hundred thirty-five thousand, four hundred ninety-one".