71287238837 has 4 divisors (see below), whose sum is σ = 71287960716. Its totient is φ = 71286516960.

The previous prime is 71287238831. The next prime is 71287238909. The reversal of 71287238837 is 73883278217.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 2860003441 + 68427235396 = 53479^2 + 261586^2 .

It is a cyclic number.

It is not a de Polignac number, because 71287238837 - 2¹² = 71287234741 is a prime.

It is a super-2 number, since 2×71287238837² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71287238831) 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, 183848 + ... + 419969.

It is an arithmetic number, because the mean of its divisors is an integer number (17821990179).

Almost surely, 2^71287238837 is an apocalyptic number.

It is an amenable number.

71287238837 is a deficient number, since it is larger than the sum of its proper divisors (721879).

71287238837 is a wasteful number, since it uses less digits than its factorization.

71287238837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 721878.

The product of its digits is 6322176, while the sum is 56.

The spelling of 71287238837 in words is "seventy-one billion, two hundred eighty-seven million, two hundred thirty-eight thousand, eight hundred thirty-seven".