615989 has 8 divisors (see below), whose sum is σ = 695520. Its totient is φ = 540400.

The previous prime is 615971. The next prime is 615997. The reversal of 615989 is 989516.

615989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-615989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (615919) 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, 647 + ... + 1284.

It is an arithmetic number, because the mean of its divisors is an integer number (86940).

2⁶¹⁵⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

615989 is a deficient number, since it is larger than the sum of its proper divisors (79531).

615989 is a wasteful number, since it uses less digits than its factorization.

615989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1971.

The product of its digits is 19440, while the sum is 38.

The square root of 615989 is about 784.8496671338. The cubic root of 615989 is about 85.0859108325.

The spelling of 615989 in words is "six hundred fifteen thousand, nine hundred eighty-nine".