71243537 has 4 divisors (see below), whose sum is σ = 73169076. Its totient is φ = 69318000.

The previous prime is 71243533. The next prime is 71243539. The reversal of 71243537 is 73534217.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73534217 = 2293 ⋅32069.

It can be written as a sum of positive squares in 2 ways, for example, as 34386496 + 36857041 = 5864^2 + 6071^2 .

It is a cyclic number.

It is not a de Polignac number, because 71243537 - 2² = 71243533 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71243533) 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, 962714 + ... + 962787.

It is an arithmetic number, because the mean of its divisors is an integer number (18292269).

Almost surely, 2^71243537 is an apocalyptic number.

It is an amenable number.

71243537 is a deficient number, since it is larger than the sum of its proper divisors (1925539).

71243537 is a wasteful number, since it uses less digits than its factorization.

71243537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1925538.

The product of its digits is 17640, while the sum is 32.

The square root of 71243537 is about 8440.5886643054. The cubic root of 71243537 is about 414.5546817524.

The spelling of 71243537 in words is "seventy-one million, two hundred forty-three thousand, five hundred thirty-seven".