71981000011 has 4 divisors (see below), whose sum is σ = 71987893992. Its totient is φ = 71974106032.

The previous prime is 71980999969. The next prime is 71981000017. The reversal of 71981000011 is 11000018917.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 71981000011 - 2¹⁵ = 71980967243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71981000017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3431305 + ... + 3452218.

It is an arithmetic number, because the mean of its divisors is an integer number (17996973498).

Almost surely, 2^71981000011 is an apocalyptic number.

71981000011 is a deficient number, since it is larger than the sum of its proper divisors (6893981).

71981000011 is a wasteful number, since it uses less digits than its factorization.

71981000011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6893980.

The product of its (nonzero) digits is 504, while the sum is 28.

Adding to 71981000011 its reverse (11000018917), we get a palindrome (82981018928).

The spelling of 71981000011 in words is "seventy-one billion, nine hundred eighty-one million, eleven", and thus it is an aban number.