1221121012001 has 24 divisors (see below), whose sum is σ = 1348212078144. Its totient is φ = 1096867840640.

The previous prime is 1221121011977. The next prime is 1221121012021. The reversal of 1221121012001 is 1002101211221.

It is a de Polignac number, because none of the positive numbers 2^k-1221121012001 is a prime.

It is a super-2 number, since 2×1221121012001² (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 (1221121012021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 150993980 + ... + 151002066.

It is an arithmetic number, because the mean of its divisors is an integer number (56175503256).

Almost surely, 2^{1221121012001} is an apocalyptic number.

1221121012001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221121012001 is a deficient number, since it is larger than the sum of its proper divisors (127091066143).

1221121012001 is an equidigital number, since it uses as much as digits as its factorization.

1221121012001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10009 (or 9920 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1221121012001 its reverse (1002101211221), we get a palindrome (2223222223222).

The spelling of 1221121012001 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-one million, twelve thousand, one".