66623645 has 8 divisors (see below), whose sum is σ = 87216480. Its totient is φ = 48453520.

The previous prime is 66623639. The next prime is 66623677. The reversal of 66623645 is 54632666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-66623645 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 66623599 and 66623608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 605615 + ... + 605724.

It is an arithmetic number, because the mean of its divisors is an integer number (10902060).

Almost surely, 2^66623645 is an apocalyptic number.

It is an amenable number.

66623645 is a deficient number, since it is larger than the sum of its proper divisors (20592835).

66623645 is a wasteful number, since it uses less digits than its factorization.

66623645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1211355.

The product of its digits is 155520, while the sum is 38.

The square root of 66623645 is about 8162.3308558279. The cubic root of 66623645 is about 405.3928921137.

The spelling of 66623645 in words is "sixty-six million, six hundred twenty-three thousand, six hundred forty-five".