81128082243 has 16 divisors (see below), whose sum is σ = 116672810240. Its totient is φ = 49847314464.

The previous prime is 81128082209. The next prime is 81128082257. The reversal of 81128082243 is 34228082118.

It is not a de Polignac number, because 81128082243 - 2¹⁷ = 81127951171 is a prime.

It is a super-2 number, since 2×81128082243² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81128082283) 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, 1592503 + ... + 1642656.

It is an arithmetic number, because the mean of its divisors is an integer number (7292050640).

Almost surely, 2^81128082243 is an apocalyptic number.

81128082243 is a deficient number, since it is larger than the sum of its proper divisors (35544727997).

81128082243 is a wasteful number, since it uses less digits than its factorization.

81128082243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3235818.

The product of its (nonzero) digits is 49152, while the sum is 39.

The spelling of 81128082243 in words is "eighty-one billion, one hundred twenty-eight million, eighty-two thousand, two hundred forty-three".