201321100991 has 2 divisors, whose sum is σ = 201321100992. Its totient is φ = 201321100990.

The previous prime is 201321100979. The next prime is 201321101029. The reversal of 201321100991 is 199001123102.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201321100991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201321100901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100660550495 + 100660550496.

It is an arithmetic number, because the mean of its divisors is an integer number (100660550496).

Almost surely, 2^201321100991 is an apocalyptic number.

201321100991 is a deficient number, since it is larger than the sum of its proper divisors (1).

201321100991 is an equidigital number, since it uses as much as digits as its factorization.

201321100991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 29.

The spelling of 201321100991 in words is "two hundred one billion, three hundred twenty-one million, one hundred thousand, nine hundred ninety-one".