66514721 has 16 divisors (see below), whose sum is σ = 82118400. Its totient is φ = 52463808.

The previous prime is 66514703. The next prime is 66514739. The reversal of 66514721 is 12741566.

It is an interprime number because it is at equal distance from previous prime (66514703) and next prime (66514739).

It is a cyclic number.

It is not a de Polignac number, because 66514721 - 2¹⁴ = 66498337 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66516721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34460 + ... + 36338.

It is an arithmetic number, because the mean of its divisors is an integer number (5132400).

Almost surely, 2^66514721 is an apocalyptic number.

It is an amenable number.

66514721 is a deficient number, since it is larger than the sum of its proper divisors (15603679).

66514721 is a wasteful number, since it uses less digits than its factorization.

66514721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2288.

The product of its digits is 10080, while the sum is 32.

The square root of 66514721 is about 8155.6557676253. The cubic root of 66514721 is about 405.1718439578.

The spelling of 66514721 in words is "sixty-six million, five hundred fourteen thousand, seven hundred twenty-one".