1221440205242 has 16 divisors (see below), whose sum is σ = 1863477614472. Its totient is φ = 600294784320.

The previous prime is 1221440205241. The next prime is 1221440205269. The reversal of 1221440205242 is 2425020441221.

It can be written as a sum of positive squares in 4 ways, for example, as 1155756153721 + 65684051521 = 1075061^2 + 256289^2 .

It is not an unprimeable number, because it can be changed into a prime (1221440205241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3267953 + ... + 3622484.

Almost surely, 2^{1221440205242} is an apocalyptic number.

1221440205242 is a deficient number, since it is larger than the sum of its proper divisors (642037409230).

1221440205242 is a wasteful number, since it uses less digits than its factorization.

1221440205242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6891953.

The product of its (nonzero) digits is 10240, while the sum is 29.

Adding to 1221440205242 its reverse (2425020441221), we get a palindrome (3646460646463).

The spelling of 1221440205242 in words is "one trillion, two hundred twenty-one billion, four hundred forty million, two hundred five thousand, two hundred forty-two".