71518556761 has 8 divisors (see below), whose sum is σ = 72506421000. Its totient is φ = 70530913152.

The previous prime is 71518556731. The next prime is 71518556801. The reversal of 71518556761 is 16765581517.

It can be written as a sum of positive squares in 4 ways, for example, as 23800775625 + 47717781136 = 154275^2 + 218444^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71518556761 is a prime.

It is a super-2 number, since 2×71518556761² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71518556699 and 71518556708.

It is not an unprimeable number, because it can be changed into a prime (71518556731) 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 7 ways as a sum of consecutive naturals, for example, 661431 + ... + 761923.

It is an arithmetic number, because the mean of its divisors is an integer number (9063302625).

Almost surely, 2^71518556761 is an apocalyptic number.

It is an amenable number.

71518556761 is a deficient number, since it is larger than the sum of its proper divisors (987864239).

71518556761 is a wasteful number, since it uses less digits than its factorization.

71518556761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110315.

The product of its digits is 1764000, while the sum is 52.

The spelling of 71518556761 in words is "seventy-one billion, five hundred eighteen million, five hundred fifty-six thousand, seven hundred sixty-one".