84187989 has 12 divisors (see below), whose sum is σ = 122116800. Its totient is φ = 55889064.

The previous prime is 84187973. The next prime is 84188017. The reversal of 84187989 is 98978148.

It is not a de Polignac number, because 84187989 - 2⁴ = 84187973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84187969) 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, 17419 + ... + 21720.

It is an arithmetic number, because the mean of its divisors is an integer number (10176400).

Almost surely, 2^84187989 is an apocalyptic number.

It is an amenable number.

84187989 is a deficient number, since it is larger than the sum of its proper divisors (37928811).

84187989 is a wasteful number, since it uses less digits than its factorization.

84187989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39384 (or 39381 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 54.

The square root of 84187989 is about 9175.4012991258. The cubic root of 84187989 is about 438.2783774860.

The spelling of 84187989 in words is "eighty-four million, one hundred eighty-seven thousand, nine hundred eighty-nine".