66404401 has 8 divisors (see below), whose sum is σ = 75960320. Its totient is φ = 56865888.

The previous prime is 66404353. The next prime is 66404419. The reversal of 66404401 is 10440466.

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

It is a cyclic number.

It is not a de Polignac number, because 66404401 - 2¹¹ = 66402353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66404101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5245 + ... + 12661.

It is an arithmetic number, because the mean of its divisors is an integer number (9495040).

Almost surely, 2^66404401 is an apocalyptic number.

It is an amenable number.

66404401 is a deficient number, since it is larger than the sum of its proper divisors (9555919).

66404401 is a wasteful number, since it uses less digits than its factorization.

66404401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8703.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 66404401 is about 8148.8895562524. The cubic root of 66404401 is about 404.9477166669.

Adding to 66404401 its reverse (10440466), we get a palindrome (76844867).

The spelling of 66404401 in words is "sixty-six million, four hundred four thousand, four hundred one".