221530101 has 64 divisors (see below), whose sum is σ = 354144000. Its totient is φ = 122653440.

The previous prime is 221530097. The next prime is 221530103. The reversal of 221530101 is 101035122.

It is not a de Polignac number, because 221530101 - 2² = 221530097 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221530103) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3631611 + ... + 3631671.

It is an arithmetic number, because the mean of its divisors is an integer number (5533500).

Almost surely, 2^221530101 is an apocalyptic number.

It is an amenable number.

221530101 is a deficient number, since it is larger than the sum of its proper divisors (132613899).

221530101 is a wasteful number, since it uses less digits than its factorization.

221530101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151 (or 125 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 221530101 is about 14883.8872946553. The cubic root of 221530101 is about 605.0773764387.

Adding to 221530101 its reverse (101035122), we get a palindrome (322565223).

The spelling of 221530101 in words is "two hundred twenty-one million, five hundred thirty thousand, one hundred one".