81282538516 has 6 divisors (see below), whose sum is σ = 142244442410. Its totient is φ = 40641269256.

The previous prime is 81282538339. The next prime is 81282538529. The reversal of 81282538516 is 61583528218.

It can be written as a sum of positive squares in only one way, i.e., 61601254416 + 19681284100 = 248196^2 + 140290^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81282538516.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10160317311 + ... + 10160317318.

Almost surely, 2^81282538516 is an apocalyptic number.

It is an amenable number.

81282538516 is a deficient number, since it is larger than the sum of its proper divisors (60961903894).

81282538516 is a wasteful number, since it uses less digits than its factorization.

81282538516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20320634633 (or 20320634631 counting only the distinct ones).

The product of its digits is 921600, while the sum is 49.

The spelling of 81282538516 in words is "eighty-one billion, two hundred eighty-two million, five hundred thirty-eight thousand, five hundred sixteen".