691554268688 has 30 divisors (see below), whose sum is σ = 1418731378974. Its totient is φ = 325430848768.

The previous prime is 691554268661. The next prime is 691554268711. The reversal of 691554268688 is 886862455196.

It can be written as a sum of positive squares in only one way, i.e., 650874605824 + 40679662864 = 806768^2 + 201692^2 .

It is a Harshad number since it is a multiple of its sum of digits (68).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13689845 + ... + 13740267.

Almost surely, 2^691554268688 is an apocalyptic number.

691554268688 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

691554268688 is an abundant number, since it is smaller than the sum of its proper divisors (727177110286).

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

691554268688 is an frugal number, since it uses more digits than its factorization.

691554268688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100871 (or 50442 counting only the distinct ones).

The product of its digits is 199065600, while the sum is 68.

Multiplying 691554268688 by its sum of digits (68), we get a square (47025690270784 = 6857528²).

691554268688 divided by its sum of digits (68) gives a square (10169915716 = 100846²).

The spelling of 691554268688 in words is "six hundred ninety-one billion, five hundred fifty-four million, two hundred sixty-eight thousand, six hundred eighty-eight".