221210122212 has 36 divisors (see below), whose sum is σ = 559484863756. Its totient is φ = 73695191040.

The previous prime is 221210122169. The next prime is 221210122219. The reversal of 221210122212 is 212221012122.

It is a happy number.

221210122212 is a `hidden beast` number, since 221 + 210 + 1 + 22 + 212 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 161044900416 + 60165221796 = 401304^2 + 245286^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is not an unprimeable number, because it can be changed into a prime (221210122219) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1664989 + ... + 1792932.

Almost surely, 2^221210122212 is an apocalyptic number.

It is an amenable number.

221210122212 is an abundant number, since it is smaller than the sum of its proper divisors (338274741544).

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

221210122212 is a wasteful number, since it uses less digits than its factorization.

221210122212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3459708 (or 3459703 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221210122212 its reverse (212221012122), we get a palindrome (433431134334).

The spelling of 221210122212 in words is "two hundred twenty-one billion, two hundred ten million, one hundred twenty-two thousand, two hundred twelve".