81180582473 has 4 divisors (see below), whose sum is σ = 81181941120. Its totient is φ = 81179223828.

The previous prime is 81180582421. The next prime is 81180582479. The reversal of 81180582473 is 37428508118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81180582473 - 2³⁴ = 64000713289 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81180582479) 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 3 ways as a sum of consecutive naturals, for example, 585365 + ... + 710642.

It is an arithmetic number, because the mean of its divisors is an integer number (20295485280).

Almost surely, 2^81180582473 is an apocalyptic number.

It is an amenable number.

81180582473 is a deficient number, since it is larger than the sum of its proper divisors (1358647).

81180582473 is a wasteful number, since it uses less digits than its factorization.

81180582473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1358646.

The product of its (nonzero) digits is 430080, while the sum is 47.

The spelling of 81180582473 in words is "eighty-one billion, one hundred eighty million, five hundred eighty-two thousand, four hundred seventy-three".