84821817 has 16 divisors (see below), whose sum is σ = 114243840. Its totient is φ = 55977600.

The previous prime is 84821791. The next prime is 84821819. The reversal of 84821817 is 71812848.

It is a happy number.

It is not a de Polignac number, because 84821817 - 2⁶ = 84821753 is a prime.

It is not an unprimeable number, because it can be changed into a prime (84821819) 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 15 ways as a sum of consecutive naturals, for example, 201267 + ... + 201687.

It is an arithmetic number, because the mean of its divisors is an integer number (7140240).

Almost surely, 2^84821817 is an apocalyptic number.

It is an amenable number.

84821817 is a deficient number, since it is larger than the sum of its proper divisors (29422023).

84821817 is a wasteful number, since it uses less digits than its factorization.

84821817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 944.

The product of its digits is 28672, while the sum is 39.

The square root of 84821817 is about 9209.8760577980. The cubic root of 84821817 is about 439.3755207946.

The spelling of 84821817 in words is "eighty-four million, eight hundred twenty-one thousand, eight hundred seventeen".