9891197901 has 32 divisors (see below), whose sum is σ = 16207358720. Its totient is φ = 5922372672.

The previous prime is 9891197887. The next prime is 9891197903. The reversal of 9891197901 is 1097911989.

It is a happy number.

It is not a de Polignac number, because 9891197901 - 2⁹ = 9891197389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9891197903) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 367825 + ... + 393798.

It is an arithmetic number, because the mean of its divisors is an integer number (506479960).

Almost surely, 2^9891197901 is an apocalyptic number.

It is an amenable number.

9891197901 is a deficient number, since it is larger than the sum of its proper divisors (6316160819).

9891197901 is a wasteful number, since it uses less digits than its factorization.

9891197901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 761682 (or 761676 counting only the distinct ones).

The product of its (nonzero) digits is 367416, while the sum is 54.

The square root of 9891197901 is about 99454.5016628207. The cubic root of 9891197901 is about 2146.5926125253.

The spelling of 9891197901 in words is "nine billion, eight hundred ninety-one million, one hundred ninety-seven thousand, nine hundred one".