66420645 has 8 divisors (see below), whose sum is σ = 106273056. Its totient is φ = 35424336.

The previous prime is 66420559. The next prime is 66420671. The reversal of 66420645 is 54602466.

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

It is not a de Polignac number, because 66420645 - 2¹² = 66416549 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a zygodrome in base 4.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2214007 + ... + 2214036.

It is an arithmetic number, because the mean of its divisors is an integer number (13284132).

Almost surely, 2^66420645 is an apocalyptic number.

It is an amenable number.

66420645 is a deficient number, since it is larger than the sum of its proper divisors (39852411).

66420645 is a wasteful number, since it uses less digits than its factorization.

66420645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4428051.

The product of its (nonzero) digits is 34560, while the sum is 33.

The square root of 66420645 is about 8149.8861955245. The cubic root of 66420645 is about 404.9807337276.

The spelling of 66420645 in words is "sixty-six million, four hundred twenty thousand, six hundred forty-five".