291220 has 12 divisors (see below), whose sum is σ = 611604. Its totient is φ = 116480.

The previous prime is 291217. The next prime is 291253. The reversal of 291220 is 22192.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 190096 + 101124 = 436^2 + 318^2 .

It is a junction number, because it is equal to n+sod(n) for n = 291194 and 291203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7261 + ... + 7300.

It is an arithmetic number, because the mean of its divisors is an integer number (50967).

2²⁹¹²²⁰ is an apocalyptic number.

291220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

291220 is an abundant number, since it is smaller than the sum of its proper divisors (320384).

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

291220 is a wasteful number, since it uses less digits than its factorization.

291220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14570 (or 14568 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 291220 is about 539.6480334440. The cubic root of 291220 is about 66.2837492694.

The spelling of 291220 in words is "two hundred ninety-one thousand, two hundred twenty".