691306669 has 4 divisors (see below), whose sum is σ = 715144860. Its totient is φ = 667468480.

The previous prime is 691306663. The next prime is 691306673. The reversal of 691306669 is 966603196.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 184606569 + 506700100 = 13587^2 + 22510^2 .

It is a cyclic number.

It is not a de Polignac number, because 691306669 - 2¹⁹ = 690782381 is a prime.

It is a super-2 number, since 2×691306669² = 955809821207751122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691306663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11919052 + ... + 11919109.

It is an arithmetic number, because the mean of its divisors is an integer number (178786215).

Almost surely, 2^691306669 is an apocalyptic number.

It is an amenable number.

691306669 is a deficient number, since it is larger than the sum of its proper divisors (23838191).

691306669 is a wasteful number, since it uses less digits than its factorization.

691306669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23838190.

The product of its (nonzero) digits is 314928, while the sum is 46.

The square root of 691306669 is about 26292.7113284271. The cubic root of 691306669 is about 884.2130401995.

The spelling of 691306669 in words is "six hundred ninety-one million, three hundred six thousand, six hundred sixty-nine".