66440544456 has 64 divisors (see below), whose sum is σ = 195140070720. Its totient is φ = 18584766720.

The previous prime is 66440544449. The next prime is 66440544461. The reversal of 66440544456 is 65444504466.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9676135 + ... + 9682998.

It is an arithmetic number, because the mean of its divisors is an integer number (3049063605).

Almost surely, 2^66440544456 is an apocalyptic number.

66440544456 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

66440544456 is an abundant number, since it is smaller than the sum of its proper divisors (128699526264).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66440544456 is a wasteful number, since it uses less digits than its factorization.

66440544456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19359166 (or 19359162 counting only the distinct ones).

The product of its (nonzero) digits is 5529600, while the sum is 48.

The spelling of 66440544456 in words is "sixty-six billion, four hundred forty million, five hundred forty-four thousand, four hundred fifty-six".