71980666 has 16 divisors (see below), whose sum is σ = 111038760. Its totient is φ = 34974720.

The previous prime is 71980663. The next prime is 71980681. The reversal of 71980666 is 66608917.

It can be written as a sum of positive squares in 4 ways, for example, as 43837641 + 28143025 = 6621^2 + 5305^2 .

It is not an unprimeable number, because it can be changed into a prime (71980663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21130 + ... + 24298.

Almost surely, 2^71980666 is an apocalyptic number.

71980666 is a deficient number, since it is larger than the sum of its proper divisors (39058094).

71980666 is a wasteful number, since it uses less digits than its factorization.

71980666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3489.

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 71980666 is about 8484.1420308715. The cubic root of 71980666 is about 415.9795239244.

The spelling of 71980666 in words is "seventy-one million, nine hundred eighty thousand, six hundred sixty-six".