221115136 has 72 divisors (see below), whose sum is σ = 484992144. Its totient is φ = 99778560.

The previous prime is 221115131. The next prime is 221115137. The reversal of 221115136 is 631511122.

221115136 = T₈₈ + T₈₉ + ... + T₁₀₉₈.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (221115131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 655960 + ... + 656296.

It is an arithmetic number, because the mean of its divisors is an integer number (6736002).

Almost surely, 2^221115136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221115136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242496072).

221115136 is an abundant number, since it is smaller than the sum of its proper divisors (263877008).

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

221115136 is a wasteful number, since it uses less digits than its factorization.

221115136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 597 (or 583 counting only the distinct ones).

The product of its digits is 360, while the sum is 22.

The square root of 221115136 is about 14869.9406858266. The cubic root of 221115136 is about 604.6993347011.

Adding to 221115136 its reverse (631511122), we get a palindrome (852626258).

The spelling of 221115136 in words is "two hundred twenty-one million, one hundred fifteen thousand, one hundred thirty-six".