8991540 has 48 divisors (see below), whose sum is σ = 27975360. Its totient is φ = 2397600.

The previous prime is 8991539. The next prime is 8991553. The reversal of 8991540 is 451998.

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 = 8991495 and 8991504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7786 + ... + 8865.

It is an arithmetic number, because the mean of its divisors is an integer number (582820).

Almost surely, 2^8991540 is an apocalyptic number.

It is an amenable number.

8991540 is an abundant number, since it is smaller than the sum of its proper divisors (18983820).

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

8991540 is a wasteful number, since it uses less digits than its factorization.

8991540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16669 (or 16661 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 8991540 is about 2998.5896684942. The cubic root of 8991540 is about 207.9431859129.

The spelling of 8991540 in words is "eight million, nine hundred ninety-one thousand, five hundred forty".