66480247 has 4 divisors (see below), whose sum is σ = 66626176. Its totient is φ = 66334320.

The previous prime is 66480233. The next prime is 66480257. The reversal of 66480247 is 74208466.

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

It is a cyclic number.

It is not a de Polignac number, because 66480247 - 2¹⁹ = 65955959 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 (66480257) 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 3 ways as a sum of consecutive naturals, for example, 72279 + ... + 73192.

It is an arithmetic number, because the mean of its divisors is an integer number (16656544).

Almost surely, 2^66480247 is an apocalyptic number.

66480247 is a deficient number, since it is larger than the sum of its proper divisors (145929).

66480247 is a wasteful number, since it uses less digits than its factorization.

66480247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145928.

The product of its (nonzero) digits is 64512, while the sum is 37.

The square root of 66480247 is about 8153.5419910613. The cubic root of 66480247 is about 405.1018328496.

The spelling of 66480247 in words is "sixty-six million, four hundred eighty thousand, two hundred forty-seven".