221513 has 4 divisors (see below), whose sum is σ = 231168. Its totient is φ = 211860.

The previous prime is 221509. The next prime is 221537. The reversal of 221513 is 315122.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 315122 = 2 ⋅157561.

It is a cyclic number.

It is not a de Polignac number, because 221513 - 2² = 221509 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221413) 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, 4793 + ... + 4838.

It is an arithmetic number, because the mean of its divisors is an integer number (57792).

2²²¹⁵¹³ is an apocalyptic number.

221513 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

221513 is a deficient number, since it is larger than the sum of its proper divisors (9655).

221513 is an equidigital number, since it uses as much as digits as its factorization.

221513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9654.

The product of its digits is 60, while the sum is 14.

The square root of 221513 is about 470.6516758708. The cubic root of 221513 is about 60.5061806403.

Adding to 221513 its reverse (315122), we get a palindrome (536635).

The spelling of 221513 in words is "two hundred twenty-one thousand, five hundred thirteen".