81800743111 has 4 divisors (see below), whose sum is σ = 86106045400. Its totient is φ = 77495440824.

The previous prime is 81800743069. The next prime is 81800743133. The reversal of 81800743111 is 11134700818.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81800743111 - 2¹³ = 81800734919 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81800743151) by changing a digit.

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, 2152651116 + ... + 2152651153.

It is an arithmetic number, because the mean of its divisors is an integer number (21526511350).

Almost surely, 2^81800743111 is an apocalyptic number.

81800743111 is a deficient number, since it is larger than the sum of its proper divisors (4305302289).

81800743111 is a wasteful number, since it uses less digits than its factorization.

81800743111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4305302288.

The product of its (nonzero) digits is 5376, while the sum is 34.

The spelling of 81800743111 in words is "eighty-one billion, eight hundred million, seven hundred forty-three thousand, one hundred eleven".