181812434013 has 18 divisors (see below), whose sum is σ = 305494362654. Its totient is φ = 103892819184.

The previous prime is 181812433931. The next prime is 181812434021. The reversal of 181812434013 is 310434218181.

181812434013 is a `hidden beast` number, since 1 + 8 + 1 + 8 + 1 + 243 + 401 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 105704314884 + 76108119129 = 325122^2 + 275877^2 .

It is not a de Polignac number, because 181812434013 - 2¹² = 181812429917 is a prime.

It is a super-2 number, since 2×181812434013² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181812430013) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 206136106 + ... + 206136987.

Almost surely, 2^181812434013 is an apocalyptic number.

It is an amenable number.

181812434013 is a deficient number, since it is larger than the sum of its proper divisors (123681928641).

181812434013 is a wasteful number, since it uses less digits than its factorization.

181812434013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412273113 (or 412273103 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The spelling of 181812434013 in words is "one hundred eighty-one billion, eight hundred twelve million, four hundred thirty-four thousand, thirteen".