84684521 has 4 divisors (see below), whose sum is σ = 84703044. Its totient is φ = 84666000.

The previous prime is 84684517. The next prime is 84684541. The reversal of 84684521 is 12548648.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 80640400 + 4044121 = 8980^2 + 2011^2 .

It is a cyclic number.

It is not a de Polignac number, because 84684521 - 2² = 84684517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84684541) 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 in 3 ways as a sum of consecutive naturals, for example, 3071 + ... + 13371.

It is an arithmetic number, because the mean of its divisors is an integer number (21175761).

Almost surely, 2^84684521 is an apocalyptic number.

It is an amenable number.

84684521 is a deficient number, since it is larger than the sum of its proper divisors (18523).

84684521 is a wasteful number, since it uses less digits than its factorization.

84684521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18522.

The product of its digits is 61440, while the sum is 38.

The square root of 84684521 is about 9202.4193014663. The cubic root of 84684521 is about 439.1383291505.

The spelling of 84684521 in words is "eighty-four million, six hundred eighty-four thousand, five hundred twenty-one".