185640040 has 16 divisors (see below), whose sum is σ = 417690180. Its totient is φ = 74256000.

The previous prime is 185640031. The next prime is 185640047. The reversal of 185640040 is 40046581.

It can be written as a sum of positive squares in 2 ways, for example, as 173765124 + 11874916 = 13182^2 + 3446^2 .

It is a junction number, because it is equal to n+sod(n) for n = 185639990 and 185640008.

It is not an unprimeable number, because it can be changed into a prime (185640047) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2320461 + ... + 2320540.

Almost surely, 2^185640040 is an apocalyptic number.

185640040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

185640040 is an abundant number, since it is smaller than the sum of its proper divisors (232050140).

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

185640040 is a wasteful number, since it uses less digits than its factorization.

185640040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4641012 (or 4641008 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 185640040 is about 13624.9785320932. The cubic root of 185640040 is about 570.4582751372.

The spelling of 185640040 in words is "one hundred eighty-five million, six hundred forty thousand, forty".