221145750 has 192 divisors, whose sum is σ = 720345600. Its totient is φ = 47822400.

The previous prime is 221145719. The next prime is 221145751. The reversal of 221145750 is 57541122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221145751) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 298881 + ... + 299619.

It is an arithmetic number, because the mean of its divisors is an integer number (3751800).

Almost surely, 2^221145750 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221145750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (360172800).

221145750 is an abundant number, since it is smaller than the sum of its proper divisors (499199850).

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

221145750 is a wasteful number, since it uses less digits than its factorization.

221145750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 788 (or 775 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 27.

The square root of 221145750 is about 14870.9700423342. The cubic root of 221145750 is about 604.7272408430.

Adding to 221145750 its reverse (57541122), we get a palindrome (278686872).

It can be divided in two parts, 2211 and 45750, that added together give a square (47961 = 219²).

The spelling of 221145750 in words is "two hundred twenty-one million, one hundred forty-five thousand, seven hundred fifty".