81575444241 has 12 divisors (see below), whose sum is σ = 118359591168. Its totient is φ = 54139755384.

The previous prime is 81575444201. The next prime is 81575444261. The reversal of 81575444241 is 14244457518.

81575444241 is a `hidden beast` number, since 8 + 157 + 54 + 442 + 4 + 1 = 666.

It is not a de Polignac number, because 81575444241 - 2⁶ = 81575444177 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (81575444201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20320725 + ... + 20324738.

It is an arithmetic number, because the mean of its divisors is an integer number (9863299264).

Almost surely, 2^81575444241 is an apocalyptic number.

It is an amenable number.

81575444241 is a deficient number, since it is larger than the sum of its proper divisors (36784146927).

81575444241 is a wasteful number, since it uses less digits than its factorization.

81575444241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40645692 (or 40645689 counting only the distinct ones).

The product of its digits is 716800, while the sum is 45.

The spelling of 81575444241 in words is "eighty-one billion, five hundred seventy-five million, four hundred forty-four thousand, two hundred forty-one".