66518007 has 4 divisors (see below), whose sum is σ = 88690680. Its totient is φ = 44345336.

The previous prime is 66517987. The next prime is 66518009. The reversal of 66518007 is 70081566.

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 66518007 - 2⁸ = 66517751 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66518009) 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, 11086332 + ... + 11086337.

It is an arithmetic number, because the mean of its divisors is an integer number (22172670).

Almost surely, 2^66518007 is an apocalyptic number.

66518007 is a deficient number, since it is larger than the sum of its proper divisors (22172673).

66518007 is a wasteful number, since it uses less digits than its factorization.

66518007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22172672.

The product of its (nonzero) digits is 10080, while the sum is 33.

The square root of 66518007 is about 8155.8572204275. The cubic root of 66518007 is about 405.1785160285.

The spelling of 66518007 in words is "sixty-six million, five hundred eighteen thousand, seven".