84134821 has 2 divisors, whose sum is σ = 84134822. Its totient is φ = 84134820.

The previous prime is 84134807. The next prime is 84134839. The reversal of 84134821 is 12843148.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43046721 + 41088100 = 6561^2 + 6410^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-84134821 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84134891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42067410 + 42067411.

It is an arithmetic number, because the mean of its divisors is an integer number (42067411).

Almost surely, 2^84134821 is an apocalyptic number.

It is an amenable number.

84134821 is a deficient number, since it is larger than the sum of its proper divisors (1).

84134821 is an equidigital number, since it uses as much as digits as its factorization.

84134821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6144, while the sum is 31.

The square root of 84134821 is about 9172.5035295714. The cubic root of 84134821 is about 438.1860947577.

Adding to 84134821 its reverse (12843148), we get a palindrome (96977969).

The spelling of 84134821 in words is "eighty-four million, one hundred thirty-four thousand, eight hundred twenty-one".