86175721 has 8 divisors (see below), whose sum is σ = 88584840. Its totient is φ = 83795712.

The previous prime is 86175707. The next prime is 86175731. The reversal of 86175721 is 12757168.

It can be written as a sum of positive squares in 4 ways, for example, as 409600 + 85766121 = 640^2 + 9261^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 86175721 - 2⁵ = 86175689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (86175731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1206 + ... + 13183.

It is an arithmetic number, because the mean of its divisors is an integer number (11073105).

Almost surely, 2^86175721 is an apocalyptic number.

It is an amenable number.

86175721 is a deficient number, since it is larger than the sum of its proper divisors (2409119).

86175721 is a wasteful number, since it uses less digits than its factorization.

86175721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14555.

The product of its digits is 23520, while the sum is 37.

The square root of 86175721 is about 9283.0879022015. The cubic root of 86175721 is about 441.7009248060.

The spelling of 86175721 in words is "eighty-six million, one hundred seventy-five thousand, seven hundred twenty-one".