9881691 has 16 divisors (see below), whose sum is σ = 14135040. Its totient is φ = 6121440.

The previous prime is 9881689. The next prime is 9881693. The reversal of 9881691 is 1961889.

9881691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (9881689) and next prime (9881693).

It is not a de Polignac number, because 9881691 - 2¹ = 9881689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9881693) 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, 1386 + ... + 4656.

It is an arithmetic number, because the mean of its divisors is an integer number (883440).

Almost surely, 2^9881691 is an apocalyptic number.

9881691 is a deficient number, since it is larger than the sum of its proper divisors (4253349).

9881691 is a wasteful number, since it uses less digits than its factorization.

9881691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3346.

The product of its digits is 31104, while the sum is 42.

The square root of 9881691 is about 3143.5157069752. The cubic root of 9881691 is about 214.5904661300.

The spelling of 9881691 in words is "nine million, eight hundred eighty-one thousand, six hundred ninety-one".