66945005 has 8 divisors (see below), whose sum is σ = 82293624. Its totient is φ = 52249600.

The previous prime is 66945001. The next prime is 66945007. The reversal of 66945005 is 50054966.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 978121 + 65966884 = 989^2 + 8122^2 .

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

It is not a de Polignac number, because 66945005 - 2² = 66945001 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66945001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 163076 + ... + 163485.

It is an arithmetic number, because the mean of its divisors is an integer number (10286703).

Almost surely, 2^66945005 is an apocalyptic number.

It is an amenable number.

66945005 is a deficient number, since it is larger than the sum of its proper divisors (15348619).

66945005 is a wasteful number, since it uses less digits than its factorization.

66945005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326607.

The product of its (nonzero) digits is 32400, while the sum is 35.

The square root of 66945005 is about 8181.9927279361. The cubic root of 66945005 is about 406.0436528407.

The spelling of 66945005 in words is "sixty-six million, nine hundred forty-five thousand, five".