1221222122178 has 16 divisors (see below), whose sum is σ = 2442498443616. Its totient is φ = 407065007520.

The previous prime is 1221222122177. The next prime is 1221222122209. The reversal of 1221222122178 is 8712212221221.

It is not an unprimeable number, because it can be changed into a prime (1221222122177) 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, 1962403 + ... + 2508678.

It is an arithmetic number, because the mean of its divisors is an integer number (152656152726).

Almost surely, 2^{1221222122178} is an apocalyptic number.

1221222122178 is an abundant number, since it is smaller than the sum of its proper divisors (1221276321438).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221222122178 is a wasteful number, since it uses less digits than its factorization.

1221222122178 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4516609.

The product of its digits is 7168, while the sum is 33.

Adding to 1221222122178 its reverse (8712212221221), we get a palindrome (9933434343399).

The spelling of 1221222122178 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-two million, one hundred twenty-two thousand, one hundred seventy-eight".