66406351 has 4 divisors (see below), whose sum is σ = 72443304. Its totient is φ = 60369400.

The previous prime is 66406339. The next prime is 66406357. The reversal of 66406351 is 15360466.

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 66406351 - 2⁹ = 66405839 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66406357) 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, 3018460 + ... + 3018481.

It is an arithmetic number, because the mean of its divisors is an integer number (18110826).

Almost surely, 2^66406351 is an apocalyptic number.

66406351 is a deficient number, since it is larger than the sum of its proper divisors (6036953).

66406351 is a wasteful number, since it uses less digits than its factorization.

66406351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6036952.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 66406351 is about 8149.0092035781. The cubic root of 66406351 is about 404.9516804620.

The spelling of 66406351 in words is "sixty-six million, four hundred six thousand, three hundred fifty-one".