1221220020011 has 4 divisors (see below), whose sum is σ = 1235933514312. Its totient is φ = 1206506525712.

The previous prime is 1221220019969. The next prime is 1221220020029. The reversal of 1221220020011 is 1100200221221.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221220020011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221220020511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7356747026 + ... + 7356747191.

It is an arithmetic number, because the mean of its divisors is an integer number (308983378578).

Almost surely, 2^{1221220020011} is an apocalyptic number.

1221220020011 is a deficient number, since it is larger than the sum of its proper divisors (14713494301).

1221220020011 is an equidigital number, since it uses as much as digits as its factorization.

1221220020011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14713494300.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 1221220020011 its reverse (1100200221221), we get a palindrome (2321420241232).

The spelling of 1221220020011 in words is "one trillion, two hundred twenty-one billion, two hundred twenty million, twenty thousand, eleven".