20121221311 has 2 divisors, whose sum is σ = 20121221312. Its totient is φ = 20121221310.

The previous prime is 20121221303. The next prime is 20121221327. The reversal of 20121221311 is 11312212102.

It is an a-pointer prime, because the next prime (20121221327) can be obtained adding 20121221311 to its sum of digits (16).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20121221311 - 2³ = 20121221303 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20121221381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060610655 + 10060610656.

It is an arithmetic number, because the mean of its divisors is an integer number (10060610656).

Almost surely, 2^20121221311 is an apocalyptic number.

20121221311 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121221311 is an equidigital number, since it uses as much as digits as its factorization.

20121221311 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 20121221311 its reverse (11312212102), we get a palindrome (31433433413).

The spelling of 20121221311 in words is "twenty billion, one hundred twenty-one million, two hundred twenty-one thousand, three hundred eleven".