71051561254321 has 4 divisors (see below), whose sum is σ = 72971873720692. Its totient is φ = 69131248787952.

The previous prime is 71051561254309. The next prime is 71051561254327. The reversal of 71051561254321 is 12345216515017.

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 32885866544400 + 38165694709921 = 5734620^2 + 6177839^2 .

It is a cyclic number.

It is not a de Polignac number, because 71051561254321 - 2³⁷ = 70914122300849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71051561254327) 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, 960156233130 + ... + 960156233203.

It is an arithmetic number, because the mean of its divisors is an integer number (18242968430173).

Almost surely, 2^{71051561254321} is an apocalyptic number.

It is an amenable number.

71051561254321 is a deficient number, since it is larger than the sum of its proper divisors (1920312466371).

71051561254321 is a wasteful number, since it uses less digits than its factorization.

71051561254321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1920312466370.

The product of its (nonzero) digits is 252000, while the sum is 43.

Adding to 71051561254321 its reverse (12345216515017), we get a palindrome (83396777769338).

The spelling of 71051561254321 in words is "seventy-one trillion, fifty-one billion, five hundred sixty-one million, two hundred fifty-four thousand, three hundred twenty-one".