66508401 has 16 divisors (see below), whose sum is σ = 91325696. Its totient is φ = 43028496.

The previous prime is 66508391. The next prime is 66508411. The reversal of 66508401 is 10480566.

It is an interprime number because it is at equal distance from previous prime (66508391) and next prime (66508411).

It is not a de Polignac number, because 66508401 - 2¹⁰ = 66507377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66508411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19446 + ... + 22608.

It is an arithmetic number, because the mean of its divisors is an integer number (5707856).

Almost surely, 2^66508401 is an apocalyptic number.

It is an amenable number.

66508401 is a deficient number, since it is larger than the sum of its proper divisors (24817295).

66508401 is a wasteful number, since it uses less digits than its factorization.

66508401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3372.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 66508401 is about 8155.2682972420. The cubic root of 66508401 is about 405.1590108731.

Adding to 66508401 its reverse (10480566), we get a palindrome (76988967).

It can be divided in two parts, 6650 and 8401, that added together give a palindrome (15051).

The spelling of 66508401 in words is "sixty-six million, five hundred eight thousand, four hundred one".