86668021 has 4 divisors (see below), whose sum is σ = 94546944. Its totient is φ = 78789100.

The previous prime is 86668013. The next prime is 86668031. The reversal of 86668021 is 12086668.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 86668021 - 2³ = 86668013 is a prime.

It is a super-2 number, since 2×86668021² = 15022691728112882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (86668031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3939445 + ... + 3939466.

It is an arithmetic number, because the mean of its divisors is an integer number (23636736).

Almost surely, 2^86668021 is an apocalyptic number.

It is an amenable number.

86668021 is a deficient number, since it is larger than the sum of its proper divisors (7878923).

86668021 is a wasteful number, since it uses less digits than its factorization.

86668021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7878922.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 86668021 is about 9309.5661015968. The cubic root of 86668021 is about 442.5404365784.

The spelling of 86668021 in words is "eighty-six million, six hundred sixty-eight thousand, twenty-one".