66686942 has 24 divisors (see below), whose sum is σ = 117234864. Its totient is φ = 28365792.

The previous prime is 66686927. The next prime is 66686947. The reversal of 66686942 is 24968666.

It is a super-2 number, since 2×66686942² = 8894296466622728, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66686947) 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 11 ways as a sum of consecutive naturals, for example, 10943 + ... + 15909.

It is an arithmetic number, because the mean of its divisors is an integer number (4884786).

Almost surely, 2^66686942 is an apocalyptic number.

66686942 is a deficient number, since it is larger than the sum of its proper divisors (50547922).

66686942 is a wasteful number, since it uses less digits than its factorization.

66686942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5120 (or 5113 counting only the distinct ones).

The product of its digits is 746496, while the sum is 47.

The square root of 66686942 is about 8166.2073204150. The cubic root of 66686942 is about 405.5212350960.

The spelling of 66686942 in words is "sixty-six million, six hundred eighty-six thousand, nine hundred forty-two".