66864224 has 36 divisors (see below), whose sum is σ = 153134604. Its totient is φ = 28655424.

The previous prime is 66864223. The next prime is 66864229. The reversal of 66864224 is 42246866.

It is a super-2 number, since 2×66864224² = 8941648902244352, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66864223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 19754 + ... + 22889.

It is an arithmetic number, because the mean of its divisors is an integer number (4253739).

Almost surely, 2^66864224 is an apocalyptic number.

It is an amenable number.

66864224 is an abundant number, since it is smaller than the sum of its proper divisors (86270380).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66864224 is a wasteful number, since it uses less digits than its factorization.

66864224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42667 (or 42652 counting only the distinct ones).

The product of its digits is 110592, while the sum is 38.

The square root of 66864224 is about 8177.0547264892. The cubic root of 66864224 is about 405.8802659212.

The spelling of 66864224 in words is "sixty-six million, eight hundred sixty-four thousand, two hundred twenty-four".