71731830985 has 4 divisors (see below), whose sum is σ = 86078197188. Its totient is φ = 57385464784.

The previous prime is 71731830983. The next prime is 71731830997. The reversal of 71731830985 is 58903813717.

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 36840579721 + 34891251264 = 191939^2 + 186792^2 .

It is a cyclic number.

It is not a de Polignac number, because 71731830985 - 2¹ = 71731830983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71731830983) 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, 7173183094 + ... + 7173183103.

It is an arithmetic number, because the mean of its divisors is an integer number (21519549297).

Almost surely, 2^71731830985 is an apocalyptic number.

It is an amenable number.

71731830985 is a deficient number, since it is larger than the sum of its proper divisors (14346366203).

71731830985 is a wasteful number, since it uses less digits than its factorization.

71731830985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14346366202.

The product of its (nonzero) digits is 1270080, while the sum is 52.

The spelling of 71731830985 in words is "seventy-one billion, seven hundred thirty-one million, eight hundred thirty thousand, nine hundred eighty-five".