84489921 has 12 divisors (see below), whose sum is σ = 122159700. Its totient is φ = 56271840.

The previous prime is 84489917. The next prime is 84489953. The reversal of 84489921 is 12998448.

84489921 is a `hidden beast` number, since 84 + 489 + 92 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 61449921 + 23040000 = 7839^2 + 4800^2 .

It is not a de Polignac number, because 84489921 - 2² = 84489917 is a prime.

It is not an unprimeable number, because it can be changed into a prime (84489901) 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 11 ways as a sum of consecutive naturals, for example, 6655 + ... + 14603.

It is an arithmetic number, because the mean of its divisors is an integer number (10179975).

Almost surely, 2^84489921 is an apocalyptic number.

It is an amenable number.

84489921 is a deficient number, since it is larger than the sum of its proper divisors (37669779).

84489921 is a wasteful number, since it uses less digits than its factorization.

84489921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9136 (or 9133 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The square root of 84489921 is about 9191.8399137496. The cubic root of 84489921 is about 438.8016999004.

The spelling of 84489921 in words is "eighty-four million, four hundred eighty-nine thousand, nine hundred twenty-one".