616601609 has 4 divisors (see below), whose sum is σ = 664032516. Its totient is φ = 569170704.

The previous prime is 616601599. The next prime is 616601651. The reversal of 616601609 is 906106616.

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 163763209 + 452838400 = 12797^2 + 21280^2 .

It is a cyclic number.

It is not a de Polignac number, because 616601609 - 2⁴ = 616601593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (616601669) 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, 23715434 + ... + 23715459.

It is an arithmetic number, because the mean of its divisors is an integer number (166008129).

Almost surely, 2^616601609 is an apocalyptic number.

It is an amenable number.

616601609 is a deficient number, since it is larger than the sum of its proper divisors (47430907).

616601609 is a wasteful number, since it uses less digits than its factorization.

616601609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47430906.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 616601609 is about 24831.4640929608. The cubic root of 616601609 is about 851.1410783215.

The spelling of 616601609 in words is "six hundred sixteen million, six hundred one thousand, six hundred nine".