221370 has 32 divisors (see below), whose sum is σ = 546048. Its totient is φ = 57408.

The previous prime is 221327. The next prime is 221393. The reversal of 221370 is 73122.

221370 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1332 + ... + 1488.

It is an arithmetic number, because the mean of its divisors is an integer number (17064).

2²²¹³⁷⁰ is an apocalyptic number.

It is a pronic number, being equal to 470×471.

It is a practical number, because each smaller number is the sum of distinct divisors of 221370, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273024).

221370 is an abundant number, since it is smaller than the sum of its proper divisors (324678).

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

221370 is a wasteful number, since it uses less digits than its factorization.

221370 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214.

The product of its (nonzero) digits is 84, while the sum is 15.

The square root of 221370 is about 470.4997343251. The cubic root of 221370 is about 60.4931577081.

Adding to 221370 its reverse (73122), we get a palindrome (294492).

The spelling of 221370 in words is "two hundred twenty-one thousand, three hundred seventy", and thus it is an iban number.