221535530 has 16 divisors (see below), whose sum is σ = 405302184. Its totient is φ = 87161280.

The previous prime is 221535529. The next prime is 221535533. The reversal of 221535530 is 35535122.

221535530 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 59151481 + 162384049 = 7691^2 + 12743^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 221535530.

It is not an unprimeable number, because it can be changed into a prime (221535533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180977 + ... + 182196.

Almost surely, 2^221535530 is an apocalyptic number.

221535530 is a deficient number, since it is larger than the sum of its proper divisors (183766654).

221535530 is a wasteful number, since it uses less digits than its factorization.

221535530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363241.

The product of its (nonzero) digits is 4500, while the sum is 26.

The square root of 221535530 is about 14884.0696719681. The cubic root of 221535530 is about 605.0823192406.

The spelling of 221535530 in words is "two hundred twenty-one million, five hundred thirty-five thousand, five hundred thirty".