9901997 has 16 divisors (see below), whose sum is σ = 11776512. Its totient is φ = 8149680.

The previous prime is 9901987. The next prime is 9901999. The reversal of 9901997 is 7991099.

It is not a de Polignac number, because 9901997 - 2⁴ = 9901981 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 (9901999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19922 + ... + 20412.

It is an arithmetic number, because the mean of its divisors is an integer number (736032).

Almost surely, 2^9901997 is an apocalyptic number.

It is an amenable number.

9901997 is a deficient number, since it is larger than the sum of its proper divisors (1874515).

9901997 is a wasteful number, since it uses less digits than its factorization.

9901997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 608.

The product of its (nonzero) digits is 45927, while the sum is 44.

The square root of 9901997 is about 3146.7438726404. The cubic root of 9901997 is about 214.7373536977.

The spelling of 9901997 in words is "nine million, nine hundred one thousand, nine hundred ninety-seven".