9997881 has 8 divisors (see below), whose sum is σ = 13690944. Its totient is φ = 6485040.

The previous prime is 9997879. The next prime is 9997913. The reversal of 9997881 is 1887999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9997881 - 2¹ = 9997879 is a prime.

It is a super-2 number, since 2×9997881² = 199915248980322, which contains 22 as substring.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (9997831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44925 + ... + 45146.

It is an arithmetic number, because the mean of its divisors is an integer number (1711368).

Almost surely, 2^9997881 is an apocalyptic number.

It is an amenable number.

9997881 is a deficient number, since it is larger than the sum of its proper divisors (3693063).

9997881 is a wasteful number, since it uses less digits than its factorization.

9997881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90111.

The product of its digits is 326592, while the sum is 51.

The square root of 9997881 is about 3161.9425990995. The cubic root of 9997881 is about 215.4282504378.

It can be divided in two parts, 9997 and 881, that added together give a triangular number (10878 = T₁₄₇).

The spelling of 9997881 in words is "nine million, nine hundred ninety-seven thousand, eight hundred eighty-one".