83856509 has 12 divisors (see below), whose sum is σ = 93003708. Its totient is φ = 75546240.

The previous prime is 83856499. The next prime is 83856527. The reversal of 83856509 is 90565838.

It can be written as a sum of positive squares in 2 ways, for example, as 40005625 + 43850884 = 6325^2 + 6622^2 .

It is a de Polignac number, because none of the positive numbers 2^k-83856509 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 83856509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (83856559) 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, 10607 + ... + 16739.

It is an arithmetic number, because the mean of its divisors is an integer number (7750309).

Almost surely, 2^83856509 is an apocalyptic number.

It is an amenable number.

83856509 is a deficient number, since it is larger than the sum of its proper divisors (9147199).

83856509 is a wasteful number, since it uses less digits than its factorization.

83856509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6268 (or 6257 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 44.

The square root of 83856509 is about 9157.3199682003. The cubic root of 83856509 is about 437.7023982151.

The spelling of 83856509 in words is "eighty-three million, eight hundred fifty-six thousand, five hundred nine".