1221202200021 has 16 divisors (see below), whose sum is σ = 1700413585920. Its totient is φ = 778119042800.

The previous prime is 1221202199977. The next prime is 1221202200041. The reversal of 1221202200021 is 1200022021221.

It is a cyclic number.

It is not a de Polignac number, because 1221202200021 - 2¹⁵ = 1221202167253 is a prime.

It is a super-2 number, since 2×1221202200021² (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 (1221202200041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6941955 + ... + 7115696.

It is an arithmetic number, because the mean of its divisors is an integer number (106275849120).

Almost surely, 2^{1221202200021} is an apocalyptic number.

It is an amenable number.

1221202200021 is a deficient number, since it is larger than the sum of its proper divisors (479211385899).

1221202200021 is a wasteful number, since it uses less digits than its factorization.

1221202200021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14058936.

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

Adding to 1221202200021 its reverse (1200022021221), we get a palindrome (2421224221242).

The spelling of 1221202200021 in words is "one trillion, two hundred twenty-one billion, two hundred two million, two hundred thousand, twenty-one".