1963648666 has 16 divisors (see below), whose sum is σ = 3399586560. Its totient is φ = 833230800.

The previous prime is 1963648639. The next prime is 1963648669. The reversal of 1963648666 is 6668463691.

It is not an unprimeable number, because it can be changed into a prime (1963648669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 692946 + ... + 695773.

It is an arithmetic number, because the mean of its divisors is an integer number (212474160).

Almost surely, 2^1963648666 is an apocalyptic number.

1963648666 is a deficient number, since it is larger than the sum of its proper divisors (1435937894).

1963648666 is a wasteful number, since it uses less digits than its factorization.

1963648666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1388829.

The product of its digits is 6718464, while the sum is 55.

The square root of 1963648666 is about 44313.0755646683. The cubic root of 1963648666 is about 1252.2410285783.

The spelling of 1963648666 in words is "one billion, nine hundred sixty-three million, six hundred forty-eight thousand, six hundred sixty-six".