8640531 has 6 divisors (see below), whose sum is σ = 12480780. Its totient is φ = 5760348.

The previous prime is 8640503. The next prime is 8640547. The reversal of 8640531 is 1350468.

It is not a de Polignac number, because 8640531 - 2¹⁰ = 8639507 is a prime.

It is a super-2 number, since 2×8640531² = 149317551923922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 8640495 and 8640504.

It is not an unprimeable number, because it can be changed into a prime (8647531) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 480021 + ... + 480038.

It is an arithmetic number, because the mean of its divisors is an integer number (2080130).

Almost surely, 2^8640531 is an apocalyptic number.

8640531 is a deficient number, since it is larger than the sum of its proper divisors (3840249).

8640531 is a wasteful number, since it uses less digits than its factorization.

8640531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 960065 (or 960062 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 8640531 is about 2939.4780148863. The cubic root of 8640531 is about 205.2013172060.

Adding to 8640531 its reverse (1350468), we get a palindrome (9990999).

It can be divided in two parts, 86405 and 31, that added together give a square (86436 = 294²).

The spelling of 8640531 in words is "eight million, six hundred forty thousand, five hundred thirty-one".