9918631 has 4 divisors (see below), whose sum is σ = 9978192. Its totient is φ = 9859072.

The previous prime is 9918617. The next prime is 9918637. The reversal of 9918631 is 1368199.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1368199 = 7 ⋅195457.

It is a cyclic number.

It is not a de Polignac number, because 9918631 - 2¹¹ = 9916583 is a prime.

It is a super-2 number, since 2×9918631² = 196758481828322, which contains 22 as substring.

It is a Duffinian number.

9918631 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9918637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29530 + ... + 29863.

It is an arithmetic number, because the mean of its divisors is an integer number (2494548).

Almost surely, 2^9918631 is an apocalyptic number.

9918631 is a deficient number, since it is larger than the sum of its proper divisors (59561).

9918631 is a wasteful number, since it uses less digits than its factorization.

9918631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59560.

The product of its digits is 11664, while the sum is 37.

The square root of 9918631 is about 3149.3858131388. The cubic root of 9918631 is about 214.8575295532.

The spelling of 9918631 in words is "nine million, nine hundred eighteen thousand, six hundred thirty-one".