1221022200021 has 16 divisors (see below), whose sum is σ = 1760986282944. Its totient is φ = 748088146944.

The previous prime is 1221022200019. The next prime is 1221022200071. The reversal of 1221022200021 is 1200022201221.

It is not a de Polignac number, because 1221022200021 - 2¹ = 1221022200019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221022200071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68952076 + ... + 68969781.

It is an arithmetic number, because the mean of its divisors is an integer number (110061642684).

Almost surely, 2^{1221022200021} is an apocalyptic number.

It is an amenable number.

1221022200021 is a deficient number, since it is larger than the sum of its proper divisors (539964082923).

1221022200021 is a wasteful number, since it uses less digits than its factorization.

1221022200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137922100.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 1221022200021 its reverse (1200022201221), we get a palindrome (2421044401242).

The spelling of 1221022200021 in words is "one trillion, two hundred twenty-one billion, twenty-two million, two hundred thousand, twenty-one".