66243644 has 6 divisors (see below), whose sum is σ = 115926384. Its totient is φ = 33121820.

The previous prime is 66243643. The next prime is 66243673. The reversal of 66243644 is 44634266.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66243641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8280452 + ... + 8280459.

It is an arithmetic number, because the mean of its divisors is an integer number (19321064).

Almost surely, 2^66243644 is an apocalyptic number.

It is an amenable number.

66243644 is a deficient number, since it is larger than the sum of its proper divisors (49682740).

66243644 is a wasteful number, since it uses less digits than its factorization.

66243644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16560915 (or 16560913 counting only the distinct ones).

The product of its digits is 82944, while the sum is 35.

The square root of 66243644 is about 8139.0198427083. The cubic root of 66243644 is about 404.6206761823.

The spelling of 66243644 in words is "sixty-six million, two hundred forty-three thousand, six hundred forty-four".