20203122991 has 2 divisors, whose sum is σ = 20203122992. Its totient is φ = 20203122990.

The previous prime is 20203122971. The next prime is 20203123027. The reversal of 20203122991 is 19922130202.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20203122991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20203122911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10101561495 + 10101561496.

It is an arithmetic number, because the mean of its divisors is an integer number (10101561496).

Almost surely, 2^20203122991 is an apocalyptic number.

20203122991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20203122991 is an equidigital number, since it uses as much as digits as its factorization.

20203122991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 31.

The spelling of 20203122991 in words is "twenty billion, two hundred three million, one hundred twenty-two thousand, nine hundred ninety-one".