1211220000221 has 16 divisors (see below), whose sum is σ = 1510336665600. Its totient is φ = 943655168880.

The previous prime is 1211220000173. The next prime is 1211220000229. The reversal of 1211220000221 is 1220000221121.

It is a cyclic number.

It is not a de Polignac number, because 1211220000221 - 2²⁶ = 1211152891357 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211220000196 and 1211220000205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211220000229) 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, 791441 + ... + 1746086.

It is an arithmetic number, because the mean of its divisors is an integer number (94396041600).

Almost surely, 2^{1211220000221} is an apocalyptic number.

1211220000221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211220000221 is a deficient number, since it is larger than the sum of its proper divisors (299116665379).

1211220000221 is a wasteful number, since it uses less digits than its factorization.

1211220000221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2543744.

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

Adding to 1211220000221 its reverse (1220000221121), we get a palindrome (2431220221342).

It can be divided in two parts, 121 and 1220000221, that multiplied together give a palindrome (147620026741).

The spelling of 1211220000221 in words is "one trillion, two hundred eleven billion, two hundred twenty million, two hundred twenty-one", and thus it is an aban number.