609685639 has 4 divisors (see below), whose sum is σ = 609832080. Its totient is φ = 609539200.

The previous prime is 609685631. The next prime is 609685651. The reversal of 609685639 is 936586906.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 936586906 = 2 ⋅468293453.

It is a cyclic number.

It is not a de Polignac number, because 609685639 - 2³ = 609685631 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 (609685631) 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, 66787 + ... + 75364.

It is an arithmetic number, because the mean of its divisors is an integer number (152458020).

Almost surely, 2^609685639 is an apocalyptic number.

609685639 is a deficient number, since it is larger than the sum of its proper divisors (146441).

609685639 is a wasteful number, since it uses less digits than its factorization.

609685639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146440.

The product of its (nonzero) digits is 2099520, while the sum is 52.

The square root of 609685639 is about 24691.8131979002. The cubic root of 609685639 is about 847.9468967985.

The spelling of 609685639 in words is "six hundred nine million, six hundred eighty-five thousand, six hundred thirty-nine".