221212350 has 48 divisors (see below), whose sum is σ = 609566640. Its totient is φ = 58989600.

The previous prime is 221212333. The next prime is 221212351. The reversal of 221212350 is 53212122.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221212351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80581 + ... + 83280.

It is an arithmetic number, because the mean of its divisors is an integer number (12699305).

Almost surely, 2^221212350 is an apocalyptic number.

221212350 is an abundant number, since it is smaller than the sum of its proper divisors (388354290).

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

221212350 is a wasteful number, since it uses less digits than its factorization.

221212350 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163882 (or 163871 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 221212350 is about 14873.2091358926. The cubic root of 221212350 is about 604.7879410703.

Adding to 221212350 its reverse (53212122), we get a palindrome (274424472).

The spelling of 221212350 in words is "two hundred twenty-one million, two hundred twelve thousand, three hundred fifty".