66688242 has 16 divisors (see below), whose sum is σ = 133459392. Its totient is φ = 22215600.

The previous prime is 66688217. The next prime is 66688261. The reversal of 66688242 is 24288666.

It is a junction number, because it is equal to n+sod(n) for n = 66688194 and 66688203.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13128 + ... + 17484.

It is an arithmetic number, because the mean of its divisors is an integer number (8341212).

Almost surely, 2^66688242 is an apocalyptic number.

66688242 is an abundant number, since it is smaller than the sum of its proper divisors (66771150).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66688242 is a wasteful number, since it uses less digits than its factorization.

66688242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6913.

The product of its digits is 221184, while the sum is 42.

The square root of 66688242 is about 8166.2869163409. The cubic root of 66688242 is about 405.5238701655.

The spelling of 66688242 in words is "sixty-six million, six hundred eighty-eight thousand, two hundred forty-two".