221270436 has 144 divisors (see below), whose sum is σ = 622702080. Its totient is φ = 65940480.

The previous prime is 221270431. The next prime is 221270459. The reversal of 221270436 is 634072122.

221270436 is a `hidden beast` number, since 221 + 2 + 7 + 0 + 436 = 666.

It is not an unprimeable number, because it can be changed into a prime (221270431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2029950 + ... + 2030058.

It is an arithmetic number, because the mean of its divisors is an integer number (4324320).

Almost surely, 2^221270436 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 221270436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (311351040).

221270436 is an abundant number, since it is smaller than the sum of its proper divisors (401431644).

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

221270436 is a wasteful number, since it uses less digits than its factorization.

221270436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274 (or 269 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 221270436 is about 14875.1617134067. The cubic root of 221270436 is about 604.8408715660.

The spelling of 221270436 in words is "two hundred twenty-one million, two hundred seventy thousand, four hundred thirty-six".