993221 has 6 divisors (see below), whose sum is σ = 1029522. Its totient is φ = 958160.

The previous prime is 993217. The next prime is 993233. The reversal of 993221 is 122399.

It can be written as a sum of positive squares in 3 ways, for example, as 376996 + 616225 = 614^2 + 785^2 .

It is not a de Polignac number, because 993221 - 2² = 993217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (993211) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 251 + ... + 1431.

It is an arithmetic number, because the mean of its divisors is an integer number (171587).

2⁹⁹³²²¹ is an apocalyptic number.

It is an amenable number.

993221 is a deficient number, since it is larger than the sum of its proper divisors (36301).

993221 is a wasteful number, since it uses less digits than its factorization.

993221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1239 (or 1210 counting only the distinct ones).

The product of its digits is 972, while the sum is 26.

The square root of 993221 is about 996.6047360915. The cubic root of 993221 is about 99.7735207922.

It can be divided in two parts, 993 and 221, that multiplied together give a triangular number (219453 = T₆₆₂).

The spelling of 993221 in words is "nine hundred ninety-three thousand, two hundred twenty-one".