81001580181 has 8 divisors (see below), whose sum is σ = 108006886464. Its totient is φ = 53998663680.

The previous prime is 81001580119. The next prime is 81001580207. The reversal of 81001580181 is 18108510018.

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

It is not a de Polignac number, because 81001580181 - 2⁷ = 81001580053 is a prime.

It is a super-2 number, since 2×81001580181² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81001380181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 516801 + ... + 655046.

It is an arithmetic number, because the mean of its divisors is an integer number (13500860808).

Almost surely, 2^81001580181 is an apocalyptic number.

It is an amenable number.

81001580181 is a deficient number, since it is larger than the sum of its proper divisors (27005306283).

81001580181 is a wasteful number, since it uses less digits than its factorization.

81001580181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1194891.

The product of its (nonzero) digits is 2560, while the sum is 33.

The spelling of 81001580181 in words is "eighty-one billion, one million, five hundred eighty thousand, one hundred eighty-one".