84354821 has 4 divisors (see below), whose sum is σ = 84376032. Its totient is φ = 84333612.

The previous prime is 84354817. The next prime is 84354847. The reversal of 84354821 is 12845348.

84354821 is nontrivially palindromic in base 2 and base 16.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 84354821 - 2² = 84354817 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84354871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2651 + ... + 13256.

It is an arithmetic number, because the mean of its divisors is an integer number (21094008).

Almost surely, 2^84354821 is an apocalyptic number.

84354821 is the 5303-rd octagonal number.

It is an amenable number.

84354821 is a deficient number, since it is larger than the sum of its proper divisors (21211).

84354821 is a wasteful number, since it uses less digits than its factorization.

84354821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21210.

The product of its digits is 30720, while the sum is 35.

The square root of 84354821 is about 9184.4880641220. The cubic root of 84354821 is about 438.5676927566.

The spelling of 84354821 in words is "eighty-four million, three hundred fifty-four thousand, eight hundred twenty-one".