80644509 has 48 divisors (see below), whose sum is σ = 134244864. Its totient is φ = 46173600.

The previous prime is 80644507. The next prime is 80644513. The reversal of 80644509 is 90544608.

80644509 is a `hidden beast` number, since 8 + 0 + 644 + 5 + 0 + 9 = 666.

It is not a de Polignac number, because 80644509 - 2¹ = 80644507 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80644507) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 243474 + ... + 243804.

It is an arithmetic number, because the mean of its divisors is an integer number (2796768).

Almost surely, 2^80644509 is an apocalyptic number.

It is an amenable number.

80644509 is a deficient number, since it is larger than the sum of its proper divisors (53600355).

80644509 is a wasteful number, since it uses less digits than its factorization.

80644509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478 (or 475 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 80644509 is about 8980.2287832772. The cubic root of 80644509 is about 432.0409715513.

Subtracting 80644509 from its reverse (90544608), we obtain a palindrome (9900099).

The spelling of 80644509 in words is "eighty million, six hundred forty-four thousand, five hundred nine".