66401403 has 8 divisors (see below), whose sum is σ = 89130000. Its totient is φ = 43970208.

The previous prime is 66401389. The next prime is 66401407. The reversal of 66401403 is 30410466.

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

It is not a de Polignac number, because 66401403 - 2¹⁸ = 66139259 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66401407) 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 7 ways as a sum of consecutive naturals, for example, 73828 + ... + 74721.

It is an arithmetic number, because the mean of its divisors is an integer number (11141250).

Almost surely, 2^66401403 is an apocalyptic number.

66401403 is a deficient number, since it is larger than the sum of its proper divisors (22728597).

66401403 is a wasteful number, since it uses less digits than its factorization.

66401403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148701.

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 66401403 is about 8148.7056027323. The cubic root of 66401403 is about 404.9416224347.

Adding to 66401403 its reverse (30410466), we get a palindrome (96811869).

The spelling of 66401403 in words is "sixty-six million, four hundred one thousand, four hundred three".