8509440 has 96 divisors (see below), whose sum is σ = 27321840. Its totient is φ = 2260992.

The previous prime is 8509433. The next prime is 8509451. The reversal of 8509440 is 449058.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×8509440² = 144821138227200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 8509398 and 8509407.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30582 + ... + 30858.

Almost surely, 2^8509440 is an apocalyptic number.

8509440 is a gapful number since it is divisible by the number (80) 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 8509440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13660920).

8509440 is an abundant number, since it is smaller than the sum of its proper divisors (18812400).

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

8509440 is a wasteful number, since it uses less digits than its factorization.

8509440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307 (or 287 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 8509440 is about 2917.0944448201. The cubic root of 8509440 is about 204.1582777802.

The spelling of 8509440 in words is "eight million, five hundred nine thousand, four hundred forty".