1979965666 has 16 divisors (see below), whose sum is σ = 3405818304. Its totient is φ = 845658864.

The previous prime is 1979965619. The next prime is 1979965667. The reversal of 1979965666 is 6665699791.

It is a junction number, because it is equal to n+sod(n) for n = 1979965598 and 1979965607.

It is not an unprimeable number, because it can be changed into a prime (1979965667) 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, 237240 + ... + 245443.

It is an arithmetic number, because the mean of its divisors is an integer number (212863644).

Almost surely, 2^1979965666 is an apocalyptic number.

1979965666 is a deficient number, since it is larger than the sum of its proper divisors (1425852638).

1979965666 is a wasteful number, since it uses less digits than its factorization.

1979965666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482985.

The product of its digits is 33067440, while the sum is 64.

The square root of 1979965666 is about 44496.8051212669. The cubic root of 1979965666 is about 1255.6999774450.

The spelling of 1979965666 in words is "one billion, nine hundred seventy-nine million, nine hundred sixty-five thousand, six hundred sixty-six".