221493 has 16 divisors (see below), whose sum is σ = 323136. Its totient is φ = 134400.

The previous prime is 221489. The next prime is 221497. The reversal of 221493 is 394122.

221493 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (221489) and next prime (221497).

It is not a de Polignac number, because 221493 - 2² = 221489 is a prime.

It is a Curzon number.

221493 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221497) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2143 + ... + 2243.

It is an arithmetic number, because the mean of its divisors is an integer number (20196).

2²²¹⁴⁹³ is an apocalyptic number.

It is an amenable number.

221493 is a deficient number, since it is larger than the sum of its proper divisors (101643).

221493 is a wasteful number, since it uses less digits than its factorization.

221493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164.

The product of its digits is 432, while the sum is 21.

The square root of 221493 is about 470.6304282555. The cubic root of 221493 is about 60.5043595884.

The spelling of 221493 in words is "two hundred twenty-one thousand, four hundred ninety-three".