221212522 has 8 divisors (see below), whose sum is σ = 343260900. Its totient is φ = 106792224.

The previous prime is 221212501. The next prime is 221212531. The reversal of 221212522 is 225212122.

221212522 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 2 ways, for example, as 215825481 + 5387041 = 14691^2 + 2321^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 221212522.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1906947 + ... + 1907062.

Almost surely, 2^221212522 is an apocalyptic number.

221212522 is a deficient number, since it is larger than the sum of its proper divisors (122048378).

221212522 is a wasteful number, since it uses less digits than its factorization.

221212522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3814040.

The product of its digits is 320, while the sum is 19.

The square root of 221212522 is about 14873.2149181003. The cubic root of 221212522 is about 604.7880978179.

Adding to 221212522 its reverse (225212122), we get a palindrome (446424644).

The spelling of 221212522 in words is "two hundred twenty-one million, two hundred twelve thousand, five hundred twenty-two".