61717617871 has 16 divisors (see below), whose sum is σ = 75968671744. Its totient is φ = 48826040544.

The previous prime is 61717617859. The next prime is 61717617937. The reversal of 61717617871 is 17871671716.

It is a cyclic number.

It is not a de Polignac number, because 61717617871 - 2¹⁵ = 61717585103 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61717617811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 904660 + ... + 970486.

It is an arithmetic number, because the mean of its divisors is an integer number (4748041984).

Almost surely, 2^61717617871 is an apocalyptic number.

61717617871 is a deficient number, since it is larger than the sum of its proper divisors (14251053873).

61717617871 is a wasteful number, since it uses less digits than its factorization.

61717617871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76150.

The product of its digits is 691488, while the sum is 52.

The spelling of 61717617871 in words is "sixty-one billion, seven hundred seventeen million, six hundred seventeen thousand, eight hundred seventy-one".