187978240 has 80 divisors (see below), whose sum is σ = 455955192. Its totient is φ = 74317824.

The previous prime is 187978223. The next prime is 187978243. The reversal of 187978240 is 42879781.

It can be written as a sum of positive squares in 4 ways, for example, as 155351296 + 32626944 = 12464^2 + 5712^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (187978243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 247942 + ... + 248698.

Almost surely, 2^187978240 is an apocalyptic number.

187978240 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 187978240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (227977596).

187978240 is an abundant number, since it is smaller than the sum of its proper divisors (267976952).

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

187978240 is an frugal number, since it uses more digits than its factorization.

187978240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 877 (or 861 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 46.

The square root of 187978240 is about 13710.5156722860. The cubic root of 187978240 is about 572.8433287033.

The spelling of 187978240 in words is "one hundred eighty-seven million, nine hundred seventy-eight thousand, two hundred forty".