181803400127 has 4 divisors (see below), whose sum is σ = 188072482920. Its totient is φ = 175534317336.

The previous prime is 181803400063. The next prime is 181803400139. The reversal of 181803400127 is 721004308181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 721004308181 = 103 ⋅7000041827.

It is a cyclic number.

It is not a de Polignac number, because 181803400127 - 2⁶ = 181803400063 is a prime.

It is a super-2 number, since 2×181803400127² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181803400187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3134541353 + ... + 3134541410.

It is an arithmetic number, because the mean of its divisors is an integer number (47018120730).

Almost surely, 2^181803400127 is an apocalyptic number.

181803400127 is a deficient number, since it is larger than the sum of its proper divisors (6269082793).

181803400127 is an equidigital number, since it uses as much as digits as its factorization.

181803400127 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6269082792.

The product of its (nonzero) digits is 10752, while the sum is 35.

The spelling of 181803400127 in words is "one hundred eighty-one billion, eight hundred three million, four hundred thousand, one hundred twenty-seven".