221408136 has 96 divisors (see below), whose sum is σ = 647089560. Its totient is φ = 68130816.

The previous prime is 221408113. The next prime is 221408177. The reversal of 221408136 is 631804122.

221408136 is a `hidden beast` number, since 221 + 408 + 1 + 36 = 666.

221408136 is digitally balanced in base 3, 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 216972900 + 4435236 = 14730^2 + 2106^2 .

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 63166 + ... + 66578.

Almost surely, 2^221408136 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 221408136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (323544780).

221408136 is an abundant number, since it is smaller than the sum of its proper divisors (425681424).

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

221408136 is a wasteful number, since it uses less digits than its factorization.

221408136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3495 (or 3488 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 221408136 is about 14879.7895146403. The cubic root of 221408136 is about 604.9663128114.

It can be divided in two parts, 22140 and 8136, that added together give a square (30276 = 174²).

The spelling of 221408136 in words is "two hundred twenty-one million, four hundred eight thousand, one hundred thirty-six".