20121221201827 has 2 divisors, whose sum is σ = 20121221201828. Its totient is φ = 20121221201826.

The previous prime is 20121221201789. The next prime is 20121221201831. The reversal of 20121221201827 is 72810212212102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20121221201827 - 2¹⁹ = 20121220677539 is a prime.

It is not a weakly prime, because it can be changed into another prime (20121221201027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060610600913 + 10060610600914.

It is an arithmetic number, because the mean of its divisors is an integer number (10060610600914).

Almost surely, 2^{20121221201827} is an apocalyptic number.

20121221201827 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121221201827 is an equidigital number, since it uses as much as digits as its factorization.

20121221201827 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3584, while the sum is 31.

Adding to 20121221201827 its reverse (72810212212102), we get a palindrome (92931433413929).

The spelling of 20121221201827 in words is "twenty trillion, one hundred twenty-one billion, two hundred twenty-one million, two hundred one thousand, eight hundred twenty-seven".