66821324 has 6 divisors (see below), whose sum is σ = 116937324. Its totient is φ = 33410660.

The previous prime is 66821323. The next prime is 66821327. The reversal of 66821324 is 42312866.

It is a super-2 number, since 2×66821324² = 8930178682225952, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66821323) 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 as a sum of consecutive naturals, namely, 8352662 + ... + 8352669.

It is an arithmetic number, because the mean of its divisors is an integer number (19489554).

Almost surely, 2^66821324 is an apocalyptic number.

It is an amenable number.

66821324 is a deficient number, since it is larger than the sum of its proper divisors (50116000).

66821324 is a wasteful number, since it uses less digits than its factorization.

66821324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16705335 (or 16705333 counting only the distinct ones).

The product of its digits is 13824, while the sum is 32.

The square root of 66821324 is about 8174.4311117043. The cubic root of 66821324 is about 405.7934432648.

The spelling of 66821324 in words is "sixty-six million, eight hundred twenty-one thousand, three hundred twenty-four".