71971581123521 has 8 divisors (see below), whose sum is σ = 73650985747680. Its totient is φ = 70292433177792.

The previous prime is 71971581123503. The next prime is 71971581123529. The reversal of 71971581123521 is 12532118517917.

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

It is a cyclic number.

It is not a de Polignac number, because 71971581123521 - 2⁶ = 71971581123457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71971581123529) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63602216 + ... + 64723913.

It is an arithmetic number, because the mean of its divisors is an integer number (9206373218460).

Almost surely, 2^{71971581123521} is an apocalyptic number.

It is an amenable number.

71971581123521 is a deficient number, since it is larger than the sum of its proper divisors (1679404624159).

71971581123521 is a wasteful number, since it uses less digits than its factorization.

71971581123521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128339215.

The product of its digits is 1058400, while the sum is 53.

The spelling of 71971581123521 in words is "seventy-one trillion, nine hundred seventy-one billion, five hundred eighty-one million, one hundred twenty-three thousand, five hundred twenty-one".