1221200011 has 2 divisors, whose sum is σ = 1221200012. Its totient is φ = 1221200010.

The previous prime is 1221199963. The next prime is 1221200017. The reversal of 1221200011 is 1100021221.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221200011 - 2¹⁵ = 1221167243 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221200017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610600005 + 610600006.

It is an arithmetic number, because the mean of its divisors is an integer number (610600006).

Almost surely, 2^1221200011 is an apocalyptic number.

1221200011 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221200011 is an equidigital number, since it uses as much as digits as its factorization.

1221200011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 1221200011 is about 34945.6722785526. The cubic root of 1221200011 is about 1068.8799561726.

Adding to 1221200011 its reverse (1100021221), we get a palindrome (2321221232).

The spelling of 1221200011 in words is "one billion, two hundred twenty-one million, two hundred thousand, eleven".