617661505061 has 4 divisors (see below), whose sum is σ = 619171680300. Its totient is φ = 616151329824.

The previous prime is 617661505001. The next prime is 617661505063. The reversal of 617661505061 is 160505166716.

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 408057774436 + 209603730625 = 638794^2 + 457825^2 .

It is a cyclic number.

It is not a de Polignac number, because 617661505061 - 2¹⁸ = 617661242917 is a prime.

It is a super-2 number, since 2×617661505061² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (617661505063) 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, 755087006 + ... + 755087823.

It is an arithmetic number, because the mean of its divisors is an integer number (154792920075).

Almost surely, 2^617661505061 is an apocalyptic number.

It is an amenable number.

617661505061 is a deficient number, since it is larger than the sum of its proper divisors (1510175239).

617661505061 is a wasteful number, since it uses less digits than its factorization.

617661505061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1510175238.

The product of its (nonzero) digits is 226800, while the sum is 44.

The spelling of 617661505061 in words is "six hundred seventeen billion, six hundred sixty-one million, five hundred five thousand, sixty-one".