221512012 has 24 divisors (see below), whose sum is σ = 400039920. Its totient is φ = 107255040.

The previous prime is 221512001. The next prime is 221512021. The reversal of 221512012 is 210215122.

It is a happy 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, 17539 + ... + 27397.

It is an arithmetic number, because the mean of its divisors is an integer number (16668330).

Almost surely, 2^221512012 is an apocalyptic number.

It is an amenable number.

221512012 is a deficient number, since it is larger than the sum of its proper divisors (178527908).

221512012 is a wasteful number, since it uses less digits than its factorization.

221512012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10041 (or 10039 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 221512012 is about 14883.2796116985. The cubic root of 221512012 is about 605.0609068295.

Adding to 221512012 its reverse (210215122), we get a palindrome (431727134).

The spelling of 221512012 in words is "two hundred twenty-one million, five hundred twelve thousand, twelve".