20121220187 has 2 divisors, whose sum is σ = 20121220188. Its totient is φ = 20121220186.

The previous prime is 20121220181. The next prime is 20121220241. The reversal of 20121220187 is 78102212102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20121220187 - 2¹² = 20121216091 is a prime.

It is not a weakly prime, because it can be changed into another prime (20121220181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060610093 + 10060610094.

It is an arithmetic number, because the mean of its divisors is an integer number (10060610094).

Almost surely, 2^20121220187 is an apocalyptic number.

20121220187 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121220187 is an equidigital number, since it uses as much as digits as its factorization.

20121220187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 896, while the sum is 26.

Adding to 20121220187 its reverse (78102212102), we get a palindrome (98223432289).

The spelling of 20121220187 in words is "twenty billion, one hundred twenty-one million, two hundred twenty thousand, one hundred eighty-seven".