71320013251 has 4 divisors (see below), whose sum is σ = 71484725032. Its totient is φ = 71155301472.

The previous prime is 71320013227. The next prime is 71320013257. The reversal of 71320013251 is 15231002317.

It is a happy number.

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 71320013251 - 2²¹ = 71317916099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71320013257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82355241 + ... + 82356106.

It is an arithmetic number, because the mean of its divisors is an integer number (17871181258).

Almost surely, 2^71320013251 is an apocalyptic number.

71320013251 is a deficient number, since it is larger than the sum of its proper divisors (164711781).

71320013251 is a wasteful number, since it uses less digits than its factorization.

71320013251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164711780.

The product of its (nonzero) digits is 1260, while the sum is 25.

Adding to 71320013251 its reverse (15231002317), we get a palindrome (86551015568).

The spelling of 71320013251 in words is "seventy-one billion, three hundred twenty million, thirteen thousand, two hundred fifty-one".