20213321122991 has 2 divisors, whose sum is σ = 20213321122992. Its totient is φ = 20213321122990.

The previous prime is 20213321122933. The next prime is 20213321123153. The reversal of 20213321122991 is 19922112331202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20213321122991 - 2⁴² = 15815274611887 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20213321142991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10106660561495 + 10106660561496.

It is an arithmetic number, because the mean of its divisors is an integer number (10106660561496).

Almost surely, 2^{20213321122991} is an apocalyptic number.

20213321122991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20213321122991 is an equidigital number, since it uses as much as digits as its factorization.

20213321122991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 38.

The spelling of 20213321122991 in words is "twenty trillion, two hundred thirteen billion, three hundred twenty-one million, one hundred twenty-two thousand, nine hundred ninety-one".