86715521 has 4 divisors (see below), whose sum is σ = 91816452. Its totient is φ = 81614592.

The previous prime is 86715493. The next prime is 86715547. The reversal of 86715521 is 12551768.

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 64625521 + 22090000 = 8039^2 + 4700^2 .

It is a cyclic number.

It is not a de Polignac number, because 86715521 - 2¹⁰ = 86714497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (86714521) 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, 2550440 + ... + 2550473.

It is an arithmetic number, because the mean of its divisors is an integer number (22954113).

Almost surely, 2^86715521 is an apocalyptic number.

It is an amenable number.

86715521 is a deficient number, since it is larger than the sum of its proper divisors (5100931).

86715521 is a wasteful number, since it uses less digits than its factorization.

86715521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5100930.

The product of its digits is 16800, while the sum is 35.

The square root of 86715521 is about 9312.1168914485. The cubic root of 86715521 is about 442.6212692831.

The spelling of 86715521 in words is "eighty-six million, seven hundred fifteen thousand, five hundred twenty-one".