66945331 has 4 divisors (see below), whose sum is σ = 67292392. Its totient is φ = 66598272.

The previous prime is 66945313. The next prime is 66945349. The reversal of 66945331 is 13354966.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (66945313) and next prime (66945349).

It is a cyclic number.

It is not a de Polignac number, because 66945331 - 2⁹ = 66944819 is a prime.

It is a super-2 number, since 2×66945331² = 8963354685399122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66945301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173241 + ... + 173626.

It is an arithmetic number, because the mean of its divisors is an integer number (16823098).

Almost surely, 2^66945331 is an apocalyptic number.

66945331 is a deficient number, since it is larger than the sum of its proper divisors (347061).

66945331 is a wasteful number, since it uses less digits than its factorization.

66945331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347060.

The product of its digits is 58320, while the sum is 37.

The square root of 66945331 is about 8182.0126497091. The cubic root of 66945331 is about 406.0443119390.

It can be divided in two parts, 66945 and 331, that added together give a palindrome (67276).

The spelling of 66945331 in words is "sixty-six million, nine hundred forty-five thousand, three hundred thirty-one".