221212111304 has 8 divisors (see below), whose sum is σ = 414772708710. Its totient is φ = 110606055648.

The previous prime is 221212111279. The next prime is 221212111409. The reversal of 221212111304 is 403111212122.

It can be written as a sum of positive squares in only one way, i.e., 182501548804 + 38710562500 = 427202^2 + 196750^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13825756949 + ... + 13825756964.

Almost surely, 2^221212111304 is an apocalyptic number.

It is an amenable number.

221212111304 is a deficient number, since it is larger than the sum of its proper divisors (193560597406).

221212111304 is a wasteful number, since it uses less digits than its factorization.

221212111304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27651513919 (or 27651513915 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 221212111304 its reverse (403111212122), we get a palindrome (624323323426).

The spelling of 221212111304 in words is "two hundred twenty-one billion, two hundred twelve million, one hundred eleven thousand, three hundred four".