81735261739 has 16 divisors (see below), whose sum is σ = 86202662400. Its totient is φ = 77284597824.

The previous prime is 81735261691. The next prime is 81735261749. The reversal of 81735261739 is 93716253718.

It is a cyclic number.

It is not a de Polignac number, because 81735261739 - 2⁹ = 81735261227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81735261749) 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, 39162954 + ... + 39165040.

It is an arithmetic number, because the mean of its divisors is an integer number (5387666400).

Almost surely, 2^81735261739 is an apocalyptic number.

81735261739 is a deficient number, since it is larger than the sum of its proper divisors (4467400661).

81735261739 is a wasteful number, since it uses less digits than its factorization.

81735261739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5082.

The product of its digits is 1905120, while the sum is 52.

The spelling of 81735261739 in words is "eighty-one billion, seven hundred thirty-five million, two hundred sixty-one thousand, seven hundred thirty-nine".