66606997 has 8 divisors (see below), whose sum is σ = 69112800. Its totient is φ = 64115184.

The previous prime is 66606979. The next prime is 66607007. The reversal of 66606997 is 79960666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66606997 - 2¹¹ = 66604949 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66606997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66607997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6754 + ... + 13372.

It is an arithmetic number, because the mean of its divisors is an integer number (8639100).

Almost surely, 2^66606997 is an apocalyptic number.

It is an amenable number.

66606997 is a deficient number, since it is larger than the sum of its proper divisors (2505803).

66606997 is a wasteful number, since it uses less digits than its factorization.

66606997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6995.

The product of its (nonzero) digits is 734832, while the sum is 49.

The square root of 66606997 is about 8161.3109853748. The cubic root of 66606997 is about 405.3591226059.

The spelling of 66606997 in words is "sixty-six million, six hundred six thousand, nine hundred ninety-seven".