81895044090 has 32 divisors (see below), whose sum is σ = 201860219520. Its totient is φ = 21248443584.

The previous prime is 81895044089. The next prime is 81895044137. The reversal of 81895044090 is 9044059818.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 36888550 + ... + 36890769.

It is an arithmetic number, because the mean of its divisors is an integer number (6308131860).

Almost surely, 2^81895044090 is an apocalyptic number.

81895044090 is an abundant number, since it is smaller than the sum of its proper divisors (119965175430).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81895044090 is a wasteful number, since it uses less digits than its factorization.

81895044090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73779366.

The product of its (nonzero) digits is 414720, while the sum is 48.

The spelling of 81895044090 in words is "eighty-one billion, eight hundred ninety-five million, forty-four thousand, ninety".