185640181840 has 40 divisors (see below), whose sum is σ = 438928915680. Its totient is φ = 72997493376.

The previous prime is 185640181799. The next prime is 185640181871. The reversal of 185640181840 is 48181046581.

185640181840 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×185640181840² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19660554 + ... + 19669993.

It is an arithmetic number, because the mean of its divisors is an integer number (10973222892).

Almost surely, 2^185640181840 is an apocalyptic number.

185640181840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

185640181840 is an abundant number, since it is smaller than the sum of its proper divisors (253288733840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

185640181840 is a wasteful number, since it uses less digits than its factorization.

185640181840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39330619 (or 39330613 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 46.

The spelling of 185640181840 in words is "one hundred eighty-five billion, six hundred forty million, one hundred eighty-one thousand, eight hundred forty".