81191577822052 has 24 divisors (see below), whose sum is σ = 142943006900736. Its totient is φ = 40351281443328.

The previous prime is 81191577822049. The next prime is 81191577822083. The reversal of 81191577822052 is 25022877519118.

It is a hoax number, since the sum of its digits (58) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 69764413 + ... + 70918660.

It is an arithmetic number, because the mean of its divisors is an integer number (5955958620864).

Almost surely, 2^{81191577822052} is an apocalyptic number.

It is an amenable number.

81191577822052 is a deficient number, since it is larger than the sum of its proper divisors (61751429078684).

81191577822052 is a wasteful number, since it uses less digits than its factorization.

81191577822052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140683947 (or 140683945 counting only the distinct ones).

The product of its (nonzero) digits is 5644800, while the sum is 58.

The spelling of 81191577822052 in words is "eighty-one trillion, one hundred ninety-one billion, five hundred seventy-seven million, eight hundred twenty-two thousand, fifty-two".