691221343122196 has 18 divisors (see below), whose sum is σ = 1284978085096958. Its totient is φ = 325280632056960.

The previous prime is 691221343122173. The next prime is 691221343122197.

691221343122196 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 3 ways, for example, as 441348080657796 + 249873262464400 = 21008286^2 + 15807380^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691221343122197) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 298971168015 + ... + 298971170326.

Almost surely, 2^{691221343122196} is an apocalyptic number.

It is an amenable number.

691221343122196 is a deficient number, since it is larger than the sum of its proper divisors (593756741974762).

691221343122196 is a wasteful number, since it uses less digits than its factorization.

691221343122196 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 597942338379 (or 597942338360 counting only the distinct ones).

The product of its digits is 1679616, while the sum is 52.

The spelling of 691221343122196 in words is "six hundred ninety-one trillion, two hundred twenty-one billion, three hundred forty-three million, one hundred twenty-two thousand, one hundred ninety-six".