66002220644 has 6 divisors (see below), whose sum is σ = 115503886134. Its totient is φ = 33001110320.

The previous prime is 66002220643. The next prime is 66002220667. The reversal of 66002220644 is 44602220066.

It can be written as a sum of positive squares in only one way, i.e., 64714272100 + 1287948544 = 254390^2 + 35888^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66002220644.

It is not an unprimeable number, because it can be changed into a prime (66002220643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8250277577 + ... + 8250277584.

It is an arithmetic number, because the mean of its divisors is an integer number (19250647689).

Almost surely, 2^66002220644 is an apocalyptic number.

It is an amenable number.

66002220644 is a deficient number, since it is larger than the sum of its proper divisors (49501665490).

66002220644 is a wasteful number, since it uses less digits than its factorization.

66002220644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16500555165 (or 16500555163 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 32.

The spelling of 66002220644 in words is "sixty-six billion, two million, two hundred twenty thousand, six hundred forty-four".