9872640 has 108 divisors (see below), whose sum is σ = 34198164. Its totient is φ = 2629632.

The previous prime is 9872623. The next prime is 9872641. The reversal of 9872640 is 462789.

9872640 is a `hidden beast` number, since 9 + 8 + 7 + 2 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 6718464 + 3154176 = 2592^2 + 1776^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 9872595 and 9872604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9872641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11092 + ... + 11948.

Almost surely, 2^9872640 is an apocalyptic number.

9872640 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9872640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17099082).

9872640 is an abundant number, since it is smaller than the sum of its proper divisors (24325524).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9872640 is a wasteful number, since it uses less digits than its factorization.

9872640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 884 (or 867 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 9872640 is about 3142.0757470182. The cubic root of 9872640 is about 214.5249290472.

The spelling of 9872640 in words is "nine million, eight hundred seventy-two thousand, six hundred forty".