66326401 has 4 divisors (see below), whose sum is σ = 70227972. Its totient is φ = 62424832.

The previous prime is 66326399. The next prime is 66326417. The reversal of 66326401 is 10462366.

66326401 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60450625 + 5875776 = 7775^2 + 2424^2 .

It is a cyclic number.

It is not a de Polignac number, because 66326401 - 2¹ = 66326399 is a prime.

It is a super-2 number, since 2×66326401² = 8798382939225602, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66326401.

It is not an unprimeable number, because it can be changed into a prime (66326431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1950760 + ... + 1950793.

It is an arithmetic number, because the mean of its divisors is an integer number (17556993).

Almost surely, 2^66326401 is an apocalyptic number.

It is an amenable number.

66326401 is a deficient number, since it is larger than the sum of its proper divisors (3901571).

66326401 is a wasteful number, since it uses less digits than its factorization.

66326401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3901570.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 66326401 is about 8144.1022218536. The cubic root of 66326401 is about 404.7891011903.

Adding to 66326401 its reverse (10462366), we get a palindrome (76788767).

The spelling of 66326401 in words is "sixty-six million, three hundred twenty-six thousand, four hundred one".