187638740 has 36 divisors (see below), whose sum is σ = 399387828. Its totient is φ = 74042880.

The previous prime is 187638739. The next prime is 187638749. The reversal of 187638740 is 47836781.

It can be written as a sum of positive squares in 2 ways, for example, as 75829264 + 111809476 = 8708^2 + 10574^2 .

It is a junction number, because it is equal to n+sod(n) for n = 187638691 and 187638700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (187638749) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 603185 + ... + 603495.

Almost surely, 2^187638740 is an apocalyptic number.

187638740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

187638740 is an abundant number, since it is smaller than the sum of its proper divisors (211749088).

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

187638740 is an equidigital number, since it uses as much as digits as its factorization.

187638740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728 (or 415 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 44.

The square root of 187638740 is about 13698.1290693291. The cubic root of 187638740 is about 572.4982577193.

The spelling of 187638740 in words is "one hundred eighty-seven million, six hundred thirty-eight thousand, seven hundred forty".