9997857 has 16 divisors (see below), whose sum is σ = 15592000. Its totient is φ = 6314112.

The previous prime is 9997831. The next prime is 9997859. The reversal of 9997857 is 7587999.

It is not a de Polignac number, because 9997857 - 2⁸ = 9997601 is a prime.

It is a Duffinian number.

9997857 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (9997859) 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, 9232 + ... + 10257.

It is an arithmetic number, because the mean of its divisors is an integer number (974500).

Almost surely, 2^9997857 is an apocalyptic number.

It is an amenable number.

9997857 is a deficient number, since it is larger than the sum of its proper divisors (5594143).

9997857 is a wasteful number, since it uses less digits than its factorization.

9997857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19517 (or 19511 counting only the distinct ones).

The product of its digits is 1428840, while the sum is 54.

The square root of 9997857 is about 3161.9388039619. The cubic root of 9997857 is about 215.4280780586.

The spelling of 9997857 in words is "nine million, nine hundred ninety-seven thousand, eight hundred fifty-seven".