66500421 has 8 divisors (see below), whose sum is σ = 95487840. Its totient is φ = 40923312.

The previous prime is 66500407. The next prime is 66500443. The reversal of 66500421 is 12400566.

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

It is not a de Polignac number, because 66500421 - 2⁵ = 66500389 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66500391 and 66500400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66500471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 852531 + ... + 852608.

It is an arithmetic number, because the mean of its divisors is an integer number (11935980).

Almost surely, 2^66500421 is an apocalyptic number.

It is an amenable number.

66500421 is a deficient number, since it is larger than the sum of its proper divisors (28987419).

66500421 is a wasteful number, since it uses less digits than its factorization.

66500421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1705155.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 66500421 is about 8154.7790282754. The cubic root of 66500421 is about 405.1428059116.

Adding to 66500421 its reverse (12400566), we get a palindrome (78900987).

The spelling of 66500421 in words is "sixty-six million, five hundred thousand, four hundred twenty-one".