691873056 has 192 divisors, whose sum is σ = 2325657600. Its totient is φ = 196017408.

The previous prime is 691873037. The next prime is 691873067. The reversal of 691873056 is 650378196.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 840261 + ... + 841083.

It is an arithmetic number, because the mean of its divisors is an integer number (12112800).

Almost surely, 2^691873056 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 691873056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1162828800).

691873056 is an abundant number, since it is smaller than the sum of its proper divisors (1633784544).

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

691873056 is a wasteful number, since it uses less digits than its factorization.

691873056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 988 (or 974 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The square root of 691873056 is about 26303.4799218659. The cubic root of 691873056 is about 884.4544526269.

The spelling of 691873056 in words is "six hundred ninety-one million, eight hundred seventy-three thousand, fifty-six".