691343388 has 36 divisors (see below), whose sum is σ = 1751637888. Its totient is φ = 229910400.

The previous prime is 691343381. The next prime is 691343449. The reversal of 691343388 is 883343196.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691343381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6588 + ... + 37763.

It is an arithmetic number, because the mean of its divisors is an integer number (48656608).

Almost surely, 2^691343388 is an apocalyptic number.

It is an amenable number.

691343388 is an abundant number, since it is smaller than the sum of its proper divisors (1060294500).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

691343388 is a wasteful number, since it uses less digits than its factorization.

691343388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44794 (or 44789 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The square root of 691343388 is about 26293.4095925196. The cubic root of 691343388 is about 884.2286950192.

The spelling of 691343388 in words is "six hundred ninety-one million, three hundred forty-three thousand, three hundred eighty-eight".