1355221 has 4 divisors (see below), whose sum is σ = 1548832. Its totient is φ = 1161612.

The previous prime is 1355219. The next prime is 1355243. The reversal of 1355221 is 1225531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1355221 - 2¹ = 1355219 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1355261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 96795 + ... + 96808.

It is an arithmetic number, because the mean of its divisors is an integer number (387208).

2^1355221 is an apocalyptic number.

It is an amenable number.

1355221 is a deficient number, since it is larger than the sum of its proper divisors (193611).

1355221 is an equidigital number, since it uses as much as digits as its factorization.

1355221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193610.

The product of its digits is 300, while the sum is 19.

The square root of 1355221 is about 1164.1395964402. The cubic root of 1355221 is about 110.6632381883.

It can be divided in two parts, 135 and 5221, that added together give a triangular number (5356 = T₁₀₃).

The spelling of 1355221 in words is "one million, three hundred fifty-five thousand, two hundred twenty-one".