691642721304 has 24 divisors (see below), whose sum is σ = 1873199037060. Its totient is φ = 230547573744.

The previous prime is 691642721267. The next prime is 691642721327. The reversal of 691642721304 is 403127246196.

691642721304 is a `hidden beast` number, since 6 + 9 + 1 + 6 + 427 + 213 + 0 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (24).

It is a self number, because there is not a number n which added to its sum of digits gives 691642721304.

It is a congruent number.

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, 4803074382 + ... + 4803074525.

Almost surely, 2^691642721304 is an apocalyptic number.

It is an amenable number.

691642721304 is an abundant number, since it is smaller than the sum of its proper divisors (1181556315756).

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

691642721304 is a wasteful number, since it uses less digits than its factorization.

691642721304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9606148919 (or 9606148912 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The spelling of 691642721304 in words is "six hundred ninety-one billion, six hundred forty-two million, seven hundred twenty-one thousand, three hundred four".