615439 has 4 divisors (see below), whose sum is σ = 671400. Its totient is φ = 559480.

The previous prime is 615437. The next prime is 615449. The reversal of 615439 is 934516.

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

It is a cyclic number.

It is not a de Polignac number, because 615439 - 2¹ = 615437 is a prime.

It is a Duffinian number.

615439 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (615431) 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, 27964 + ... + 27985.

It is an arithmetic number, because the mean of its divisors is an integer number (167850).

2⁶¹⁵⁴³⁹ is an apocalyptic number.

615439 is a deficient number, since it is larger than the sum of its proper divisors (55961).

615439 is a wasteful number, since it uses less digits than its factorization.

615439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55960.

The product of its digits is 3240, while the sum is 28.

The square root of 615439 is about 784.4992033138. The cubic root of 615439 is about 85.0605796519.

The spelling of 615439 in words is "six hundred fifteen thousand, four hundred thirty-nine".