86667721 has 24 divisors (see below), whose sum is σ = 107105280. Its totient is φ = 69727392.

The previous prime is 86667709. The next prime is 86667731. The reversal of 86667721 is 12776668.

It is a de Polignac number, because none of the positive numbers 2^k-86667721 is a prime.

It is a super-2 number, since 2×86667721² = 15022587726667682, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86667701) 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 23 ways as a sum of consecutive naturals, for example, 117871 + ... + 118603.

It is an arithmetic number, because the mean of its divisors is an integer number (4462720).

Almost surely, 2^86667721 is an apocalyptic number.

It is an amenable number.

86667721 is a deficient number, since it is larger than the sum of its proper divisors (20437559).

86667721 is a wasteful number, since it uses less digits than its factorization.

86667721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 893 (or 886 counting only the distinct ones).

The product of its digits is 169344, while the sum is 43.

The square root of 86667721 is about 9309.5499891241. The cubic root of 86667721 is about 442.5399259622.

The spelling of 86667721 in words is "eighty-six million, six hundred sixty-seven thousand, seven hundred twenty-one".