221240 has 16 divisors (see below), whose sum is σ = 497880. Its totient is φ = 88480.

The previous prime is 221239. The next prime is 221251. The reversal of 221240 is 42122.

221240 = 110² + 111² + ... + 125².

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2726 + ... + 2805.

2²²¹²⁴⁰ is an apocalyptic number.

221240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221240 is an abundant number, since it is smaller than the sum of its proper divisors (276640).

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

221240 is a wasteful number, since it uses less digits than its factorization.

221240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5542 (or 5538 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 11.

The square root of 221240 is about 470.3615630555. The cubic root of 221240 is about 60.4813138111.

Adding to 221240 its reverse (42122), we get a palindrome (263362).

The spelling of 221240 in words is "two hundred twenty-one thousand, two hundred forty", and thus it is an iban number.