66778042 has 8 divisors (see below), whose sum is σ = 101809332. Its totient is φ = 32841600.

The previous prime is 66778037. The next prime is 66778043. The reversal of 66778042 is 24087766.

It can be written as a sum of positive squares in 2 ways, for example, as 56987401 + 9790641 = 7549^2 + 3129^2 .

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 = 66777986 and 66778004.

It is not an unprimeable number, because it can be changed into a prime (66778043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 273559 + ... + 273802.

Almost surely, 2^66778042 is an apocalyptic number.

66778042 is a deficient number, since it is larger than the sum of its proper divisors (35031290).

66778042 is a wasteful number, since it uses less digits than its factorization.

66778042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 547424.

The product of its (nonzero) digits is 112896, while the sum is 40.

The square root of 66778042 is about 8171.7832815121. The cubic root of 66778042 is about 405.7058098356.

The spelling of 66778042 in words is "sixty-six million, seven hundred seventy-eight thousand, forty-two".