20012550391 has 2 divisors, whose sum is σ = 20012550392. Its totient is φ = 20012550390.

The previous prime is 20012550319. The next prime is 20012550421. The reversal of 20012550391 is 19305521002.

Together with previous prime (20012550319) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20012550391 - 2¹⁷ = 20012419319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20012550191) 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, 10006275195 + 10006275196.

It is an arithmetic number, because the mean of its divisors is an integer number (10006275196).

Almost surely, 2^20012550391 is an apocalyptic number.

20012550391 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012550391 is an equidigital number, since it uses as much as digits as its factorization.

20012550391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2700, while the sum is 28.

The spelling of 20012550391 in words is "twenty billion, twelve million, five hundred fifty thousand, three hundred ninety-one".