1211221012 has 6 divisors (see below), whose sum is σ = 2119636778. Its totient is φ = 605610504.

The previous prime is 1211220991. The next prime is 1211221019. The reversal of 1211221012 is 2101221121.

It can be written as a sum of positive squares in only one way, i.e., 699285136 + 511935876 = 26444^2 + 22626^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1211220983 and 1211221001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211221019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 151402623 + ... + 151402630.

Almost surely, 2^1211221012 is an apocalyptic number.

It is an amenable number.

1211221012 is a deficient number, since it is larger than the sum of its proper divisors (908415766).

1211221012 is a wasteful number, since it uses less digits than its factorization.

1211221012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302805257 (or 302805255 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 1211221012 is about 34802.6006499514. The cubic root of 1211221012 is about 1065.9605496349.

Adding to 1211221012 its reverse (2101221121), we get a palindrome (3312442133).

It can be divided in two parts, 12112 and 21012, that added together give a square (33124 = 182²).

The spelling of 1211221012 in words is "one billion, two hundred eleven million, two hundred twenty-one thousand, twelve".