291065940 has 192 divisors, whose sum is σ = 1040256000. Its totient is φ = 66821760.

The previous prime is 291065909. The next prime is 291065947. The reversal of 291065940 is 49560192.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 291065895 and 291065904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (291065947) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 111571 + ... + 114149.

It is an arithmetic number, because the mean of its divisors is an integer number (5418000).

Almost surely, 2^291065940 is an apocalyptic number.

291065940 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 291065940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (520128000).

291065940 is an abundant number, since it is smaller than the sum of its proper divisors (749190060).

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

291065940 is a wasteful number, since it uses less digits than its factorization.

291065940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2627 (or 2619 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 291065940 is about 17060.6547353846. The cubic root of 291065940 is about 662.7205882267.

The spelling of 291065940 in words is "two hundred ninety-one million, sixty-five thousand, nine hundred forty".