66966840 has 48 divisors (see below), whose sum is σ = 217643400. Its totient is φ = 17857728.

The previous prime is 66966821. The next prime is 66966841. The reversal of 66966840 is 4866966.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66966841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 92650 + ... + 93369.

Almost surely, 2^66966840 is an apocalyptic number.

66966840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66966840 is an abundant number, since it is smaller than the sum of its proper divisors (150676560).

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

66966840 is a wasteful number, since it uses less digits than its factorization.

66966840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186036 (or 186029 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The square root of 66966840 is about 8183.3269517966. The cubic root of 66966840 is about 406.0877935470.

The spelling of 66966840 in words is "sixty-six million, nine hundred sixty-six thousand, eight hundred forty".