1221121212001 has 16 divisors (see below), whose sum is σ = 1249668163584. Its totient is φ = 1192683747024.

The previous prime is 1221121211983. The next prime is 1221121212067. The reversal of 1221121212001 is 1002121211221.

It is a cyclic number.

It is not a de Polignac number, because 1221121212001 - 2⁹ = 1221121211489 is a prime.

It is a super-2 number, since 2×1221121212001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221121242001) 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, 46803706 + ... + 46829788.

It is an arithmetic number, because the mean of its divisors is an integer number (78104260224).

Almost surely, 2^{1221121212001} is an apocalyptic number.

It is an amenable number.

1221121212001 is a deficient number, since it is larger than the sum of its proper divisors (28546951583).

1221121212001 is a wasteful number, since it uses less digits than its factorization.

1221121212001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28140.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221121212001 its reverse (1002121211221), we get a palindrome (2223242423222).

The spelling of 1221121212001 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred twelve thousand, one".