1221221020011 has 8 divisors (see below), whose sum is σ = 1638284232000. Its totient is φ = 809152577352.

The previous prime is 1221221020009. The next prime is 1221221020039. The reversal of 1221221020011 is 1100201221221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221221020011 - 2¹ = 1221221020009 is a prime.

It is a super-4 number, since 4×1221221020011⁴ (a number of 49 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221221020511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1248691761 + ... + 1248692738.

It is an arithmetic number, because the mean of its divisors is an integer number (204785529000).

Almost surely, 2^{1221221020011} is an apocalyptic number.

1221221020011 is a deficient number, since it is larger than the sum of its proper divisors (417063211989).

1221221020011 is a wasteful number, since it uses less digits than its factorization.

1221221020011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2497384665.

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

Adding to 1221221020011 its reverse (1100201221221), we get a palindrome (2321422241232).

The spelling of 1221221020011 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, twenty thousand, eleven".