81801041511 has 32 divisors (see below), whose sum is σ = 126200148480. Its totient is φ = 46162289664.

The previous prime is 81801041467. The next prime is 81801041513. The reversal of 81801041511 is 11514010818.

It is not a de Polignac number, because 81801041511 - 2⁹ = 81801040999 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81801041513) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5376531 + ... + 5391723.

It is an arithmetic number, because the mean of its divisors is an integer number (3943754640).

Almost surely, 2^81801041511 is an apocalyptic number.

81801041511 is a deficient number, since it is larger than the sum of its proper divisors (44399106969).

81801041511 is a wasteful number, since it uses less digits than its factorization.

81801041511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18375.

The product of its (nonzero) digits is 1280, while the sum is 30.

The spelling of 81801041511 in words is "eighty-one billion, eight hundred one million, forty-one thousand, five hundred eleven".