291381648 has 80 divisors (see below), whose sum is σ = 790425600. Its totient is φ = 92373120.

The previous prime is 291381619. The next prime is 291381653. The reversal of 291381648 is 846183192.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 86133 + ... + 89451.

It is an arithmetic number, because the mean of its divisors is an integer number (9880320).

Almost surely, 2^291381648 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 291381648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395212800).

291381648 is an abundant number, since it is smaller than the sum of its proper divisors (499043952).

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

291381648 is a wasteful number, since it uses less digits than its factorization.

291381648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3420 (or 3414 counting only the distinct ones).

The product of its digits is 82944, while the sum is 42.

The square root of 291381648 is about 17069.9047449012. The cubic root of 291381648 is about 662.9601108019.

The spelling of 291381648 in words is "two hundred ninety-one million, three hundred eighty-one thousand, six hundred forty-eight".