81750189911 has 16 divisors (see below), whose sum is σ = 91115760288. Its totient is φ = 72862156800.

The previous prime is 81750189877. The next prime is 81750189919. The reversal of 81750189911 is 11998105718.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 81750189911 - 2¹⁸ = 81749927767 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81750189911.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81750189919) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 738905 + ... + 842306.

It is an arithmetic number, because the mean of its divisors is an integer number (5694735018).

Almost surely, 2^81750189911 is an apocalyptic number.

81750189911 is a deficient number, since it is larger than the sum of its proper divisors (9365570377).

81750189911 is a wasteful number, since it uses less digits than its factorization.

81750189911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1581362.

The product of its (nonzero) digits is 181440, while the sum is 50.

The spelling of 81750189911 in words is "eighty-one billion, seven hundred fifty million, one hundred eighty-nine thousand, nine hundred eleven".