616309 has 4 divisors (see below), whose sum is σ = 633004. Its totient is φ = 599616.

The previous prime is 616307. The next prime is 616313. The reversal of 616309 is 903616.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 592900 + 23409 = 770^2 + 153^2 .

It is a cyclic number.

It is not a de Polignac number, because 616309 - 2¹ = 616307 is a prime.

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

It is a Duffinian number.

616309 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (616307) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8292 + ... + 8365.

It is an arithmetic number, because the mean of its divisors is an integer number (158251).

2⁶¹⁶³⁰⁹ is an apocalyptic number.

It is an amenable number.

616309 is a deficient number, since it is larger than the sum of its proper divisors (16695).

616309 is a wasteful number, since it uses less digits than its factorization.

616309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16694.

The product of its (nonzero) digits is 972, while the sum is 25.

The square root of 616309 is about 785.0535013615. The cubic root of 616309 is about 85.1006420361.

The spelling of 616309 in words is "six hundred sixteen thousand, three hundred nine".