66386661 has 16 divisors (see below), whose sum is σ = 96702528. Its totient is φ = 40176000.

The previous prime is 66386659. The next prime is 66386669. The reversal of 66386661 is 16668366.

It is not a de Polignac number, because 66386661 - 2¹ = 66386659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66386669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35961 + ... + 37761.

It is an arithmetic number, because the mean of its divisors is an integer number (6043908).

Almost surely, 2^66386661 is an apocalyptic number.

It is an amenable number.

66386661 is a deficient number, since it is larger than the sum of its proper divisors (30315867).

66386661 is a wasteful number, since it uses less digits than its factorization.

66386661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2932.

The product of its digits is 186624, while the sum is 42.

The square root of 66386661 is about 8147.8009916787. The cubic root of 66386661 is about 404.9116527304.

The spelling of 66386661 in words is "sixty-six million, three hundred eighty-six thousand, six hundred sixty-one".