66649007 has 4 divisors (see below), whose sum is σ = 66815616. Its totient is φ = 66482400.

The previous prime is 66648983. The next prime is 66649043. The reversal of 66649007 is 70094666.

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 66649007 - 2¹⁰ = 66647983 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 (66649307) 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, 82703 + ... + 83504.

It is an arithmetic number, because the mean of its divisors is an integer number (16703904).

Almost surely, 2^66649007 is an apocalyptic number.

66649007 is a deficient number, since it is larger than the sum of its proper divisors (166609).

66649007 is a wasteful number, since it uses less digits than its factorization.

66649007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166608.

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 66649007 is about 8163.8843083424. The cubic root of 66649007 is about 405.4443266564. Note that the first 3 decimals are identical.

The spelling of 66649007 in words is "sixty-six million, six hundred forty-nine thousand, seven".