185138919640 has 32 divisors (see below), whose sum is σ = 416714129280. Its totient is φ = 74028623872.

The previous prime is 185138919631. The next prime is 185138919649. The reversal of 185138919640 is 46919831581.

It is a happy number.

185138919640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (185138919631) and next prime (185138919649).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (185138919649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 730504 + ... + 950743.

It is an arithmetic number, because the mean of its divisors is an integer number (13022316540).

Almost surely, 2^185138919640 is an apocalyptic number.

185138919640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

185138919640 is an abundant number, since it is smaller than the sum of its proper divisors (231575209640).

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

185138919640 is a wasteful number, since it uses less digits than its factorization.

185138919640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1684011 (or 1684007 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 55.

The spelling of 185138919640 in words is "one hundred eighty-five billion, one hundred thirty-eight million, nine hundred nineteen thousand, six hundred forty".