66467821 has 4 divisors (see below), whose sum is σ = 75963232. Its totient is φ = 56972412.

The previous prime is 66467803. The next prime is 66467827. The reversal of 66467821 is 12876466.

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 not a de Polignac number, because 66467821 - 2⁵ = 66467789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66467827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4747695 + ... + 4747708.

It is an arithmetic number, because the mean of its divisors is an integer number (18990808).

Almost surely, 2^66467821 is an apocalyptic number.

It is an amenable number.

66467821 is a deficient number, since it is larger than the sum of its proper divisors (9495411).

66467821 is an equidigital number, since it uses as much as digits as its factorization.

66467821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9495410.

The product of its digits is 96768, while the sum is 40.

The square root of 66467821 is about 8152.7799553281. The cubic root of 66467821 is about 405.0765917228.

The spelling of 66467821 in words is "sixty-six million, four hundred sixty-seven thousand, eight hundred twenty-one".