20012220251 has 2 divisors, whose sum is σ = 20012220252. Its totient is φ = 20012220250.

The previous prime is 20012220169. The next prime is 20012220281. The reversal of 20012220251 is 15202221002.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20012220251 is a prime.

It is not a weakly prime, because it can be changed into another prime (20012220281) 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, 10006110125 + 10006110126.

It is an arithmetic number, because the mean of its divisors is an integer number (10006110126).

Almost surely, 2^20012220251 is an apocalyptic number.

20012220251 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012220251 is an equidigital number, since it uses as much as digits as its factorization.

20012220251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 17.

Adding to 20012220251 its reverse (15202221002), we get a palindrome (35214441253).

The spelling of 20012220251 in words is "twenty billion, twelve million, two hundred twenty thousand, two hundred fifty-one".