81767517549 has 8 divisors (see below), whose sum is σ = 110042267040. Its totient is φ = 54002223216.

The previous prime is 81767517539. The next prime is 81767517553. The reversal of 81767517549 is 94571576718.

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

It is not a de Polignac number, because 81767517549 - 2¹⁵ = 81767484781 is a prime.

It is a super-2 number, since 2×81767517549² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81767517492 and 81767517501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81767517509) 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, 127363414 + ... + 127364055.

It is an arithmetic number, because the mean of its divisors is an integer number (13755283380).

Almost surely, 2^81767517549 is an apocalyptic number.

It is an amenable number.

81767517549 is a deficient number, since it is larger than the sum of its proper divisors (28274749491).

81767517549 is a wasteful number, since it uses less digits than its factorization.

81767517549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254727579.

The product of its digits is 14817600, while the sum is 60.

The spelling of 81767517549 in words is "eighty-one billion, seven hundred sixty-seven million, five hundred seventeen thousand, five hundred forty-nine".