1001220122221 has 16 divisors (see below), whose sum is σ = 1121296958208. Its totient is φ = 886081996800.

The previous prime is 1001220122197. The next prime is 1001220122261. The reversal of 1001220122221 is 1222210221001.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-1001220122221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001220122195 and 1001220122204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001220122261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2188596 + ... + 2606221.

It is an arithmetic number, because the mean of its divisors is an integer number (70081059888).

Almost surely, 2^{1001220122221} is an apocalyptic number.

1001220122221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1001220122221 is a deficient number, since it is larger than the sum of its proper divisors (120076835987).

1001220122221 is a wasteful number, since it uses less digits than its factorization.

1001220122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4795332.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1001220122221 its reverse (1222210221001), we get a palindrome (2223430343222).

The spelling of 1001220122221 in words is "one trillion, one billion, two hundred twenty million, one hundred twenty-two thousand, two hundred twenty-one".