691269149 has 4 divisors (see below), whose sum is σ = 698113500. Its totient is φ = 684424800.

The previous prime is 691269121. The next prime is 691269151. The reversal of 691269149 is 941962196.

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 656281924 + 34987225 = 25618^2 + 5915^2 .

It is a cyclic number.

It is not a de Polignac number, because 691269149 - 2²⁸ = 422833693 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691269119) 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 in 3 ways as a sum of consecutive naturals, for example, 3422024 + ... + 3422225.

It is an arithmetic number, because the mean of its divisors is an integer number (174528375).

Almost surely, 2^691269149 is an apocalyptic number.

It is an amenable number.

691269149 is a deficient number, since it is larger than the sum of its proper divisors (6844351).

691269149 is a wasteful number, since it uses less digits than its factorization.

691269149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6844350.

The product of its digits is 209952, while the sum is 47.

The square root of 691269149 is about 26291.9978130229. The cubic root of 691269149 is about 884.1970433079.

The spelling of 691269149 in words is "six hundred ninety-one million, two hundred sixty-nine thousand, one hundred forty-nine".