691308803568 has 160 divisors (see below), whose sum is σ = 1893536663040. Its totient is φ = 216726451200.

The previous prime is 691308803567. The next prime is 691308803579. The reversal of 691308803568 is 865308803196.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691308803567) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 87492418 + ... + 87500318.

It is an arithmetic number, because the mean of its divisors is an integer number (11834604144).

Almost surely, 2^691308803568 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691308803568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (946768331520).

691308803568 is an abundant number, since it is smaller than the sum of its proper divisors (1202227859472).

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

691308803568 is a wasteful number, since it uses less digits than its factorization.

691308803568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8615 (or 8609 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 57.

The spelling of 691308803568 in words is "six hundred ninety-one billion, three hundred eight million, eight hundred three thousand, five hundred sixty-eight".