66824121 has 48 divisors (see below), whose sum is σ = 116183040. Its totient is φ = 33359040.

The previous prime is 66824117. The next prime is 66824129. The reversal of 66824121 is 12142866.

It is not a de Polignac number, because 66824121 - 2² = 66824117 is a prime.

It is a super-4 number, since 4×66824121⁴ (a number of 32 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (66824129) 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 47 ways as a sum of consecutive naturals, for example, 66936 + ... + 67926.

It is an arithmetic number, because the mean of its divisors is an integer number (2420480).

Almost surely, 2^66824121 is an apocalyptic number.

It is an amenable number.

66824121 is a deficient number, since it is larger than the sum of its proper divisors (49358919).

66824121 is a wasteful number, since it uses less digits than its factorization.

66824121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1046 (or 1033 counting only the distinct ones).

The product of its digits is 4608, while the sum is 30.

The square root of 66824121 is about 8174.6021921559. The cubic root of 66824121 is about 405.7991050724.

Adding to 66824121 its reverse (12142866), we get a palindrome (78966987).

The spelling of 66824121 in words is "sixty-six million, eight hundred twenty-four thousand, one hundred twenty-one".