81175810946 has 8 divisors (see below), whose sum is σ = 121772061180. Its totient is φ = 40585123888.

The previous prime is 81175810871. The next prime is 81175810967. The reversal of 81175810946 is 64901857118.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 81051243025 + 124567921 = 284695^2 + 11161^2 .

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

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81175810894 and 81175810903.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1354121 + ... + 1412796.

Almost surely, 2^81175810946 is an apocalyptic number.

81175810946 is a deficient number, since it is larger than the sum of its proper divisors (40596250234).

81175810946 is a wasteful number, since it uses less digits than its factorization.

81175810946 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2781588.

The product of its (nonzero) digits is 483840, while the sum is 50.

The spelling of 81175810946 in words is "eighty-one billion, one hundred seventy-five million, eight hundred ten thousand, nine hundred forty-six".