221392 has 20 divisors (see below), whose sum is σ = 436356. Its totient is φ = 108800.

The previous prime is 221327. The next prime is 221393. The reversal of 221392 is 293122.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 179776 + 41616 = 424^2 + 204^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221393) by changing a digit.

221392 is an untouchable number, because it is not equal to the sum of proper divisors of any 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, 1548 + ... + 1684.

2²²¹³⁹² is an apocalyptic number.

It is an amenable number.

221392 is a deficient number, since it is larger than the sum of its proper divisors (214964).

221392 is a wasteful number, since it uses less digits than its factorization.

221392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246 (or 240 counting only the distinct ones).

The product of its digits is 216, while the sum is 19.

The square root of 221392 is about 470.5231131411. The cubic root of 221392 is about 60.4951616011.

The spelling of 221392 in words is "two hundred twenty-one thousand, three hundred ninety-two".