84657521 has 16 divisors (see below), whose sum is σ = 96445440. Its totient is φ = 73664640.

The previous prime is 84657499. The next prime is 84657523. The reversal of 84657521 is 12575648.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-84657521 is a prime.

It is not an unprimeable number, because it can be changed into a prime (84657523) 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, 56816 + ... + 58286.

It is an arithmetic number, because the mean of its divisors is an integer number (6027840).

Almost surely, 2^84657521 is an apocalyptic number.

It is an amenable number.

84657521 is a deficient number, since it is larger than the sum of its proper divisors (11787919).

84657521 is a wasteful number, since it uses less digits than its factorization.

84657521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736.

The product of its digits is 67200, while the sum is 38.

The square root of 84657521 is about 9200.9521789867. The cubic root of 84657521 is about 439.0916539727.

The spelling of 84657521 in words is "eighty-four million, six hundred fifty-seven thousand, five hundred twenty-one".