81542862313 has 6 divisors (see below), whose sum is σ = 89629757882. Its totient is φ = 74129874720.

The previous prime is 81542862311. The next prime is 81542862353. The reversal of 81542862313 is 31326824518.

It can be written as a sum of positive squares in only one way, i.e., 41915191824 + 39627670489 = 204732^2 + 199067^2 .

It is not a de Polignac number, because 81542862313 - 2¹ = 81542862311 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81542862313.

It is not an unprimeable number, because it can be changed into a prime (81542862311) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 336953856 + ... + 336954097.

Almost surely, 2^81542862313 is an apocalyptic number.

It is an amenable number.

81542862313 is a deficient number, since it is larger than the sum of its proper divisors (8086895569).

81542862313 is a wasteful number, since it uses less digits than its factorization.

81542862313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673907975 (or 673907964 counting only the distinct ones).

The product of its digits is 276480, while the sum is 43.

The spelling of 81542862313 in words is "eighty-one billion, five hundred forty-two million, eight hundred sixty-two thousand, three hundred thirteen".