66688042 has 8 divisors (see below), whose sum is σ = 105916356. Its totient is φ = 31382592.

The previous prime is 66688033. The next prime is 66688057. The reversal of 66688042 is 24088666.

It can be written as a sum of positive squares in 2 ways, for example, as 64786401 + 1901641 = 8049^2 + 1379^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 66687986 and 66688004.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 980673 + ... + 980740.

Almost surely, 2^66688042 is an apocalyptic number.

66688042 is a deficient number, since it is larger than the sum of its proper divisors (39228314).

66688042 is a wasteful number, since it uses less digits than its factorization.

66688042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1961432.

The product of its (nonzero) digits is 110592, while the sum is 40.

The square root of 66688042 is about 8166.2746708643. The cubic root of 66688042 is about 405.5234647724.

The spelling of 66688042 in words is "sixty-six million, six hundred eighty-eight thousand, forty-two".