1221122121011 has 4 divisors (see below), whose sum is σ = 1315054591872. Its totient is φ = 1127189650152.

The previous prime is 1221122120987. The next prime is 1221122121029. The reversal of 1221122121011 is 1101212211221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221122121011 - 2¹⁴ = 1221122104627 is a prime.

It is a super-2 number, since 2×1221122121011² (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 (1221122121071) 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 3 ways as a sum of consecutive naturals, for example, 46966235411 + ... + 46966235436.

It is an arithmetic number, because the mean of its divisors is an integer number (328763647968).

Almost surely, 2^{1221122121011} is an apocalyptic number.

1221122121011 is a deficient number, since it is larger than the sum of its proper divisors (93932470861).

1221122121011 is an equidigital number, since it uses as much as digits as its factorization.

1221122121011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93932470860.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1221122121011 its reverse (1101212211221), we get a palindrome (2322334332232).

The spelling of 1221122121011 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-two million, one hundred twenty-one thousand, eleven".