221001212 has 24 divisors (see below), whose sum is σ = 390224016. Its totient is φ = 109513728.

The previous prime is 221001167. The next prime is 221001223. The reversal of 221001212 is 212100122.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 221001193 and 221001202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 360218 + ... + 360830.

It is an arithmetic number, because the mean of its divisors is an integer number (16259334).

Almost surely, 2^221001212 is an apocalyptic number.

It is an amenable number.

221001212 is a deficient number, since it is larger than the sum of its proper divisors (169222804).

221001212 is a wasteful number, since it uses less digits than its factorization.

221001212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277 (or 1275 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 221001212 is about 14866.1095112339. The cubic root of 221001212 is about 604.5954648305.

Adding to 221001212 its reverse (212100122), we get a palindrome (433101334).

The spelling of 221001212 in words is "two hundred twenty-one million, one thousand, two hundred twelve".