7216509 has 8 divisors (see below), whose sum is σ = 9721600. Its totient is φ = 4761216.

The previous prime is 7216507. The next prime is 7216513. The reversal of 7216509 is 9056127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 7216509 - 2¹ = 7216507 is a prime.

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

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7216507) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12109 + ... + 12690.

It is an arithmetic number, because the mean of its divisors is an integer number (1215200).

Almost surely, 2^7216509 is an apocalyptic number.

It is an amenable number.

7216509 is a deficient number, since it is larger than the sum of its proper divisors (2505091).

7216509 is a wasteful number, since it uses less digits than its factorization.

7216509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24899.

The product of its (nonzero) digits is 3780, while the sum is 30.

The square root of 7216509 is about 2686.3560821306. The cubic root of 7216509 is about 193.2453500441.

The spelling of 7216509 in words is "seven million, two hundred sixteen thousand, five hundred nine".