221312040212 has 6 divisors (see below), whose sum is σ = 387296070378. Its totient is φ = 110656020104.

The previous prime is 221312040181. The next prime is 221312040233. The reversal of 221312040212 is 212040213122.

It can be written as a sum of positive squares in only one way, i.e., 163833895696 + 57478144516 = 404764^2 + 239746^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27664005023 + ... + 27664005030.

It is an arithmetic number, because the mean of its divisors is an integer number (64549345063).

Almost surely, 2^221312040212 is an apocalyptic number.

It is an amenable number.

221312040212 is a deficient number, since it is larger than the sum of its proper divisors (165984030166).

221312040212 is a wasteful number, since it uses less digits than its factorization.

221312040212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55328010057 (or 55328010055 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 221312040212 its reverse (212040213122), we get a palindrome (433352253334).

The spelling of 221312040212 in words is "two hundred twenty-one billion, three hundred twelve million, forty thousand, two hundred twelve".