81620537182735 has 16 divisors (see below), whose sum is σ = 104695866152640. Its totient is φ = 60934101986560.

The previous prime is 81620537182693. The next prime is 81620537182739. The reversal of 81620537182735 is 53728173502618.

It is a de Polignac number, because none of the positive numbers 2^k-81620537182735 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81620537182735.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81620537182739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8655407500 + ... + 8655416929.

It is an arithmetic number, because the mean of its divisors is an integer number (6543491634540).

Almost surely, 2^{81620537182735} is an apocalyptic number.

81620537182735 is a deficient number, since it is larger than the sum of its proper divisors (23075328969905).

81620537182735 is a wasteful number, since it uses less digits than its factorization.

81620537182735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17310824498.

The product of its (nonzero) digits is 16934400, while the sum is 58.

The spelling of 81620537182735 in words is "eighty-one trillion, six hundred twenty billion, five hundred thirty-seven million, one hundred eighty-two thousand, seven hundred thirty-five".