1221112200021 has 64 divisors (see below), whose sum is σ = 2129944043520. Its totient is φ = 605352268800.

The previous prime is 1221112199927. The next prime is 1221112200037. The reversal of 1221112200021 is 1200022111221.

It is not a de Polignac number, because 1221112200021 - 2⁷ = 1221112199893 is a prime.

It is a super-2 number, since 2×1221112200021² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221112200421) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2181805 + ... + 2683746.

It is an arithmetic number, because the mean of its divisors is an integer number (33280375680).

Almost surely, 2^{1221112200021} is an apocalyptic number.

It is an amenable number.

1221112200021 is a deficient number, since it is larger than the sum of its proper divisors (908831843499).

1221112200021 is a wasteful number, since it uses less digits than its factorization.

1221112200021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4865634.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1221112200021 its reverse (1200022111221), we get a palindrome (2421134311242).

The spelling of 1221112200021 in words is "one trillion, two hundred twenty-one billion, one hundred twelve million, two hundred thousand, twenty-one".