1221202011021 has 16 divisors (see below), whose sum is σ = 1724079795264. Its totient is φ = 766231111424.

The previous prime is 1221202011011. The next prime is 1221202011041. The reversal of 1221202011021 is 1201102021221.

It is a cyclic number.

It is not a de Polignac number, because 1221202011021 - 2⁵ = 1221202010989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221202011011) 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, 3356026 + ... + 3702068.

It is an arithmetic number, because the mean of its divisors is an integer number (107754987204).

Almost surely, 2^{1221202011021} is an apocalyptic number.

It is an amenable number.

1221202011021 is a deficient number, since it is larger than the sum of its proper divisors (502877784243).

1221202011021 is a wasteful number, since it uses less digits than its factorization.

1221202011021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415260.

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

Adding to 1221202011021 its reverse (1201102021221), we get a palindrome (2422304032242).

The spelling of 1221202011021 in words is "one trillion, two hundred twenty-one billion, two hundred two million, eleven thousand, twenty-one".