66613207 has 4 divisors (see below), whose sum is σ = 67361760. Its totient is φ = 65864656.

The previous prime is 66613201. The next prime is 66613219. The reversal of 66613207 is 70231666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70231666 = 2 ⋅35115833.

It is a cyclic number.

It is not a de Polignac number, because 66613207 - 2¹¹ = 66611159 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 (66613201) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 374143 + ... + 374320.

It is an arithmetic number, because the mean of its divisors is an integer number (16840440).

Almost surely, 2^66613207 is an apocalyptic number.

66613207 is a deficient number, since it is larger than the sum of its proper divisors (748553).

66613207 is an equidigital number, since it uses as much as digits as its factorization.

66613207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 748552.

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 66613207 is about 8161.6914300897. The cubic root of 66613207 is about 405.3717198906.

The spelling of 66613207 in words is "sixty-six million, six hundred thirteen thousand, two hundred seven".