66945444654 has 32 divisors (see below), whose sum is σ = 150010436736. Its totient is φ = 19738213920.

The previous prime is 66945444613. The next prime is 66945444673. The reversal of 66945444654 is 45644454966.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 66945444594 and 66945444603.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 13704652 + ... + 13709535.

It is an arithmetic number, because the mean of its divisors is an integer number (4687826148).

Almost surely, 2^66945444654 is an apocalyptic number.

66945444654 is an abundant number, since it is smaller than the sum of its proper divisors (83064992082).

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

66945444654 is a wasteful number, since it uses less digits than its factorization.

66945444654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27414240.

The product of its digits is 49766400, while the sum is 57.

The spelling of 66945444654 in words is "sixty-six billion, nine hundred forty-five million, four hundred forty-four thousand, six hundred fifty-four".