66247287 has 4 divisors (see below), whose sum is σ = 88329720. Its totient is φ = 44164856.

The previous prime is 66247277. The next prime is 66247289. The reversal of 66247287 is 78274266.

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 66247287 - 2⁴ = 66247271 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66247289) 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, 11041212 + ... + 11041217.

It is an arithmetic number, because the mean of its divisors is an integer number (22082430).

Almost surely, 2^66247287 is an apocalyptic number.

66247287 is a deficient number, since it is larger than the sum of its proper divisors (22082433).

66247287 is a wasteful number, since it uses less digits than its factorization.

66247287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22082432.

The product of its digits is 225792, while the sum is 42.

The square root of 66247287 is about 8139.2436380784. The cubic root of 66247287 is about 404.6280932768.

The spelling of 66247287 in words is "sixty-six million, two hundred forty-seven thousand, two hundred eighty-seven".