1221222168406 has 4 divisors (see below), whose sum is σ = 1831833252612. Its totient is φ = 610611084202.

The previous prime is 1221222168403. The next prime is 1221222168409. The reversal of 1221222168406 is 6048612221221.

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

It is an interprime number because it is at equal distance from previous prime (1221222168403) and next prime (1221222168409).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221222168403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305305542100 + ... + 305305542103.

It is an arithmetic number, because the mean of its divisors is an integer number (457958313153).

Almost surely, 2^{1221222168406} is an apocalyptic number.

1221222168406 is a deficient number, since it is larger than the sum of its proper divisors (610611084206).

1221222168406 is an equidigital number, since it uses as much as digits as its factorization.

1221222168406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610611084205.

The product of its (nonzero) digits is 36864, while the sum is 37.

Adding to 1221222168406 its reverse (6048612221221), we get a palindrome (7269834389627).

The spelling of 1221222168406 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-two million, one hundred sixty-eight thousand, four hundred six".