284638987 has 2 divisors, whose sum is σ = 284638988. Its totient is φ = 284638986.

The previous prime is 284638969. The next prime is 284639101. The reversal of 284638987 is 789836482.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 284638987 - 2²⁷ = 150421259 is a prime.

It is not a weakly prime, because it can be changed into another prime (284638967) 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 as a sum of consecutive naturals, namely, 142319493 + 142319494.

It is an arithmetic number, because the mean of its divisors is an integer number (142319494).

Almost surely, 2^284638987 is an apocalyptic number.

284638987 is a deficient number, since it is larger than the sum of its proper divisors (1).

284638987 is an equidigital number, since it uses as much as digits as its factorization.

284638987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4644864, while the sum is 55.

The square root of 284638987 is about 16871.2473457062. The cubic root of 284638987 is about 657.8064512361.

The spelling of 284638987 in words is "two hundred eighty-four million, six hundred thirty-eight thousand, nine hundred eighty-seven".