71658667881 has 6 divisors (see below), whose sum is σ = 103506964730. Its totient is φ = 47772445248.

The previous prime is 71658667879. The next prime is 71658667897. The reversal of 71658667881 is 18876685617.

It can be written as a sum of positive squares in only one way, i.e., 39585081600 + 32073586281 = 198960^2 + 179091^2 .

It is not a de Polignac number, because 71658667881 - 2¹ = 71658667879 is a prime.

It is a super-2 number, since 2×71658667881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71658667811) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3981037096 + ... + 3981037113.

Almost surely, 2^71658667881 is an apocalyptic number.

It is an amenable number.

71658667881 is a deficient number, since it is larger than the sum of its proper divisors (31848296849).

71658667881 is a wasteful number, since it uses less digits than its factorization.

71658667881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7962074215 (or 7962074212 counting only the distinct ones).

The product of its digits is 27095040, while the sum is 63.

The spelling of 71658667881 in words is "seventy-one billion, six hundred fifty-eight million, six hundred sixty-seven thousand, eight hundred eighty-one".