66444444465 has 32 divisors (see below), whose sum is σ = 122385288960. Its totient is φ = 30152884224.

The previous prime is 66444444463. The next prime is 66444444541. The reversal of 66444444465 is 56444444466.

It is not a de Polignac number, because 66444444465 - 2¹ = 66444444463 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66444444463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2295120 + ... + 2323889.

It is an arithmetic number, because the mean of its divisors is an integer number (3824540280).

Almost surely, 2^66444444465 is an apocalyptic number.

It is an amenable number.

66444444465 is a deficient number, since it is larger than the sum of its proper divisors (55940844495).

66444444465 is a wasteful number, since it uses less digits than its factorization.

66444444465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4619161.

The product of its digits is 17694720, while the sum is 51.

Subtracting from 66444444465 its reverse (56444444466), we obtain a palindrome (9999999999).

The spelling of 66444444465 in words is "sixty-six billion, four hundred forty-four million, four hundred forty-four thousand, four hundred sixty-five".