187887139 has 4 divisors (see below), whose sum is σ = 204967800. Its totient is φ = 170806480.

The previous prime is 187887121. The next prime is 187887149. The reversal of 187887139 is 931788781.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 187887139 - 2⁵ = 187887107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (187887149) 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, 8540314 + ... + 8540335.

It is an arithmetic number, because the mean of its divisors is an integer number (51241950).

Almost surely, 2^187887139 is an apocalyptic number.

187887139 is a deficient number, since it is larger than the sum of its proper divisors (17080661).

187887139 is a wasteful number, since it uses less digits than its factorization.

187887139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17080660.

The product of its digits is 677376, while the sum is 52.

The square root of 187887139 is about 13707.1929657388. The cubic root of 187887139 is about 572.7507736060.

The spelling of 187887139 in words is "one hundred eighty-seven million, eight hundred eighty-seven thousand, one hundred thirty-nine".