1221222168442 has 4 divisors (see below), whose sum is σ = 1831833252666. Its totient is φ = 610611084220.

The previous prime is 1221222168409. The next prime is 1221222168443. The reversal of 1221222168442 is 2448612221221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1083558165481 + 137664002961 = 1040941^2 + 371031^2 .

It is not an unprimeable number, because it can be changed into a prime (1221222168443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305305542109 + ... + 305305542112.

Almost surely, 2^{1221222168442} is an apocalyptic number.

1221222168442 is a deficient number, since it is larger than the sum of its proper divisors (610611084224).

1221222168442 is an equidigital number, since it uses as much as digits as its factorization.

1221222168442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 610611084223.

The product of its digits is 49152, while the sum is 37.

Adding to 1221222168442 its reverse (2448612221221), we get a palindrome (3669834389663).

The spelling of 1221222168442 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-two million, one hundred sixty-eight thousand, four hundred forty-two".