71243145 has 20 divisors (see below), whose sum is σ = 127710660. Its totient is φ = 37996128.

The previous prime is 71243119. The next prime is 71243173. The reversal of 71243145 is 54134217.

It can be written as a sum of positive squares in 2 ways, for example, as 8088336 + 63154809 = 2844^2 + 7947^2 .

It is not a de Polignac number, because 71243145 - 2⁵ = 71243113 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 87550 + ... + 88359.

It is an arithmetic number, because the mean of its divisors is an integer number (6385533).

Almost surely, 2^71243145 is an apocalyptic number.

It is an amenable number.

71243145 is a deficient number, since it is larger than the sum of its proper divisors (56467515).

71243145 is a wasteful number, since it uses less digits than its factorization.

71243145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175926 (or 175917 counting only the distinct ones).

The product of its digits is 3360, while the sum is 27.

The square root of 71243145 is about 8440.5654431442. The cubic root of 71243145 is about 414.5539214227.

The spelling of 71243145 in words is "seventy-one million, two hundred forty-three thousand, one hundred forty-five".