9901901 has 2 divisors, whose sum is σ = 9901902. Its totient is φ = 9901900.

The previous prime is 9901889. The next prime is 9901981. The reversal of 9901901 is 1091099.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5175625 + 4726276 = 2275^2 + 2174^2 .

It is a cyclic number.

It is not a de Polignac number, because 9901901 - 2¹⁸ = 9639757 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9901981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4950950 + 4950951.

It is an arithmetic number, because the mean of its divisors is an integer number (4950951).

Almost surely, 2^9901901 is an apocalyptic number.

It is an amenable number.

9901901 is a deficient number, since it is larger than the sum of its proper divisors (1).

9901901 is an equidigital number, since it uses as much as digits as its factorization.

9901901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 729, while the sum is 29.

The square root of 9901901 is about 3146.7286187404. The cubic root of 9901901 is about 214.7366597349.

The spelling of 9901901 in words is "nine million, nine hundred one thousand, nine hundred one".