71512737257 has 4 divisors (see below), whose sum is σ = 77013717060. Its totient is φ = 66011757456.

The previous prime is 71512737211. The next prime is 71512737269. The reversal of 71512737257 is 75273721517.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21291479056 + 50221258201 = 145916^2 + 224101^2 .

It is a cyclic number.

It is not a de Polignac number, because 71512737257 - 2⁶ = 71512737193 is a prime.

It is a super-2 number, since 2×71512737257² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71512737277) 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, 2750489882 + ... + 2750489907.

It is an arithmetic number, because the mean of its divisors is an integer number (19253429265).

Almost surely, 2^71512737257 is an apocalyptic number.

It is an amenable number.

71512737257 is a deficient number, since it is larger than the sum of its proper divisors (5500979803).

71512737257 is a wasteful number, since it uses less digits than its factorization.

71512737257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5500979802.

The product of its digits is 720300, while the sum is 47.

The spelling of 71512737257 in words is "seventy-one billion, five hundred twelve million, seven hundred thirty-seven thousand, two hundred fifty-seven".