691343420123 has 2 divisors, whose sum is σ = 691343420124. Its totient is φ = 691343420122.

The previous prime is 691343420083. The next prime is 691343420197. The reversal of 691343420123 is 321024343196.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 691343420123 - 2¹⁴ = 691343403739 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (691343420023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345671710061 + 345671710062.

It is an arithmetic number, because the mean of its divisors is an integer number (345671710062).

Almost surely, 2^691343420123 is an apocalyptic number.

691343420123 is a deficient number, since it is larger than the sum of its proper divisors (1).

691343420123 is an equidigital number, since it uses as much as digits as its factorization.

691343420123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 93312, while the sum is 38.

The spelling of 691343420123 in words is "six hundred ninety-one billion, three hundred forty-three million, four hundred twenty thousand, one hundred twenty-three".