617581561 has 8 divisors (see below), whose sum is σ = 620812640. Its totient is φ = 614358432.

The previous prime is 617581543. The next prime is 617581571. The reversal of 617581561 is 165185716.

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

It is a cyclic number.

It is not a de Polignac number, because 617581561 - 2²¹ = 615484409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (617581571) 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, 207661 + ... + 210613.

It is an arithmetic number, because the mean of its divisors is an integer number (77601580).

Almost surely, 2^617581561 is an apocalyptic number.

It is an amenable number.

617581561 is a deficient number, since it is larger than the sum of its proper divisors (3231079).

617581561 is a wasteful number, since it uses less digits than its factorization.

617581561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3975.

The product of its digits is 50400, while the sum is 40.

The square root of 617581561 is about 24851.1883216880. The cubic root of 617581561 is about 851.5917398827.

The spelling of 617581561 in words is "six hundred seventeen million, five hundred eighty-one thousand, five hundred sixty-one".