691349389 has 4 divisors (see below), whose sum is σ = 691817056. Its totient is φ = 690881724.

The previous prime is 691349377. The next prime is 691349401. The reversal of 691349389 is 983943196.

691349389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (691349377) and next prime (691349401).

It is a cyclic number.

It is not a de Polignac number, because 691349389 - 2⁷ = 691349261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691349089) 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, 231609 + ... + 234574.

It is an arithmetic number, because the mean of its divisors is an integer number (172954264).

Almost surely, 2^691349389 is an apocalyptic number.

It is an amenable number.

691349389 is a deficient number, since it is larger than the sum of its proper divisors (467667).

691349389 is a wasteful number, since it uses less digits than its factorization.

691349389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 467666.

The product of its digits is 1259712, while the sum is 52.

The square root of 691349389 is about 26293.5237083203. The cubic root of 691349389 is about 884.2312534395.

The spelling of 691349389 in words is "six hundred ninety-one million, three hundred forty-nine thousand, three hundred eighty-nine".