66401443 has 4 divisors (see below), whose sum is σ = 66418240. Its totient is φ = 66384648.

The previous prime is 66401441. The next prime is 66401471. The reversal of 66401443 is 34410466.

It is a happy number.

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 66401443 - 2¹ = 66401441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66401441) 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, 1153 + ... + 11581.

It is an arithmetic number, because the mean of its divisors is an integer number (16604560).

Almost surely, 2^66401443 is an apocalyptic number.

66401443 is a deficient number, since it is larger than the sum of its proper divisors (16797).

66401443 is a wasteful number, since it uses less digits than its factorization.

66401443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16796.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 66401443 is about 8148.7080571094. The cubic root of 66401443 is about 404.9417037465.

The spelling of 66401443 in words is "sixty-six million, four hundred one thousand, four hundred forty-three".