1221001100212 has 12 divisors (see below), whose sum is σ = 2137220440516. Its totient is φ = 610366688640.

The previous prime is 1221001100197. The next prime is 1221001100213. The reversal of 1221001100212 is 2120011001221.

It can be written as a sum of positive squares in 2 ways, for example, as 694282231696 + 526718868516 = 833236^2 + 725754^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1221001100192 and 1221001100201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221001100213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33444843 + ... + 33481330.

Almost surely, 2^{1221001100212} is an apocalyptic number.

It is an amenable number.

1221001100212 is a deficient number, since it is larger than the sum of its proper divisors (916219340304).

1221001100212 is a wasteful number, since it uses less digits than its factorization.

1221001100212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66930738 (or 66930736 counting only the distinct ones).

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

Adding to 1221001100212 its reverse (2120011001221), we get a palindrome (3341012101433).

The spelling of 1221001100212 in words is "one trillion, two hundred twenty-one billion, one million, one hundred thousand, two hundred twelve".