81742486647 has 8 divisors (see below), whose sum is σ = 109375106944. Its totient is φ = 54302428728.

The previous prime is 81742486619. The next prime is 81742486663. The reversal of 81742486647 is 74668424718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81742486647 - 2⁶ = 81742486583 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81742486607) 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 7 ways as a sum of consecutive naturals, for example, 48139603 + ... + 48141300.

It is an arithmetic number, because the mean of its divisors is an integer number (13671888368).

Almost surely, 2^81742486647 is an apocalyptic number.

81742486647 is a deficient number, since it is larger than the sum of its proper divisors (27632620297).

81742486647 is a wasteful number, since it uses less digits than its factorization.

81742486647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96281189.

The product of its digits is 14450688, while the sum is 57.

The spelling of 81742486647 in words is "eighty-one billion, seven hundred forty-two million, four hundred eighty-six thousand, six hundred forty-seven".