71320729 has 8 divisors (see below), whose sum is σ = 75698280. Its totient is φ = 66963456.

The previous prime is 71320727. The next prime is 71320747. The reversal of 71320729 is 92702317.

It can be written as a sum of positive squares in 4 ways, for example, as 8277129 + 63043600 = 2877^2 + 7940^2 .

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 71320729 - 2¹ = 71320727 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71320729.

It is not an unprimeable number, because it can be changed into a prime (71320721) 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, 2517 + ... + 12205.

It is an arithmetic number, because the mean of its divisors is an integer number (9462285).

Almost surely, 2^71320729 is an apocalyptic number.

It is an amenable number.

71320729 is a deficient number, since it is larger than the sum of its proper divisors (4377551).

71320729 is a wasteful number, since it uses less digits than its factorization.

71320729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10139.

The product of its (nonzero) digits is 5292, while the sum is 31.

The square root of 71320729 is about 8445.1600932132. The cubic root of 71320729 is about 414.7043503207.

The spelling of 71320729 in words is "seventy-one million, three hundred twenty thousand, seven hundred twenty-nine".