1221210353444 has 24 divisors (see below), whose sum is σ = 2163762854400. Its totient is φ = 603038394720.

The previous prime is 1221210353443. The next prime is 1221210353471. The reversal of 1221210353444 is 4443530121221.

It is a super-2 number, since 2×1221210353444² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1221210353444.

It is not an unprimeable number, because it can be changed into a prime (1221210353443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5643599 + ... + 5855990.

It is an arithmetic number, because the mean of its divisors is an integer number (90156785600).

Almost surely, 2^{1221210353444} is an apocalyptic number.

It is an amenable number.

1221210353444 is a deficient number, since it is larger than the sum of its proper divisors (942552500956).

1221210353444 is a wasteful number, since it uses less digits than its factorization.

1221210353444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11499923 (or 11499921 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 32.

Adding to 1221210353444 its reverse (4443530121221), we get a palindrome (5664740474665).

The spelling of 1221210353444 in words is "one trillion, two hundred twenty-one billion, two hundred ten million, three hundred fifty-three thousand, four hundred forty-four".