291987240 has 128 divisors (see below), whose sum is σ = 950382720. Its totient is φ = 71475200.

The previous prime is 291987217. The next prime is 291987251. The reversal of 291987240 is 42789192.

It is a junction number, because it is equal to n+sod(n) for n = 291987192 and 291987201.

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, 81895 + ... + 85385.

It is an arithmetic number, because the mean of its divisors is an integer number (7424865).

Almost surely, 2^291987240 is an apocalyptic number.

291987240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 291987240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (475191360).

291987240 is an abundant number, since it is smaller than the sum of its proper divisors (658395480).

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

291987240 is a wasteful number, since it uses less digits than its factorization.

291987240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3563 (or 3559 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The square root of 291987240 is about 17087.6341252966. The cubic root of 291987240 is about 663.4190799036.

The spelling of 291987240 in words is "two hundred ninety-one million, nine hundred eighty-seven thousand, two hundred forty".