291561696 has 216 divisors, whose sum is σ = 917227584. Its totient is φ = 87736320.

The previous prime is 291561667. The next prime is 291561703. The reversal of 291561696 is 696165192.

It is a happy number.

291561696 is a `hidden beast` number, since 29 + 1 + 5 + 616 + 9 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2580136 + ... + 2580248.

It is an arithmetic number, because the mean of its divisors is an integer number (4246424).

Almost surely, 2^291561696 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 291561696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (458613792).

291561696 is an abundant number, since it is smaller than the sum of its proper divisors (625665888).

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

291561696 is a wasteful number, since it uses less digits than its factorization.

291561696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194 (or 166 counting only the distinct ones).

The product of its digits is 174960, while the sum is 45.

The square root of 291561696 is about 17075.1777735987. The cubic root of 291561696 is about 663.0966328578.

The spelling of 291561696 in words is "two hundred ninety-one million, five hundred sixty-one thousand, six hundred ninety-six".