188144640 has 176 divisors, whose sum is σ = 669123360. Its totient is φ = 50135040.

The previous prime is 188144617. The next prime is 188144659. The reversal of 188144640 is 46441881.

188144640 is a `hidden beast` number, since 1 + 8 + 8 + 1 + 4 + 4 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 188144595 and 188144604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 137560 + ... + 138920.

Almost surely, 2^188144640 is an apocalyptic number.

188144640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 188144640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (334561680).

188144640 is an abundant number, since it is smaller than the sum of its proper divisors (480978720).

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

188144640 is a wasteful number, since it uses less digits than its factorization.

188144640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1395 (or 1371 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

The square root of 188144640 is about 13716.5826647894. The cubic root of 188144640 is about 573.0123075123.

The spelling of 188144640 in words is "one hundred eighty-eight million, one hundred forty-four thousand, six hundred forty".