187431139 has 4 divisors (see below), whose sum is σ = 214207024. Its totient is φ = 160655256.

The previous prime is 187431121. The next prime is 187431149. The reversal of 187431139 is 931134781.

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 187431139 - 2¹³ = 187422947 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 187431098 and 187431107.

It is not an unprimeable number, because it can be changed into a prime (187431149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13387932 + ... + 13387945.

It is an arithmetic number, because the mean of its divisors is an integer number (53551756).

Almost surely, 2^187431139 is an apocalyptic number.

187431139 is a deficient number, since it is larger than the sum of its proper divisors (26775885).

187431139 is an equidigital number, since it uses as much as digits as its factorization.

187431139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26775884.

The product of its digits is 18144, while the sum is 37.

The square root of 187431139 is about 13690.5492585214. The cubic root of 187431139 is about 572.2870449929.

The spelling of 187431139 in words is "one hundred eighty-seven million, four hundred thirty-one thousand, one hundred thirty-nine".