66820940 has 24 divisors (see below), whose sum is σ = 142303392. Its totient is φ = 26351360.

The previous prime is 66820889. The next prime is 66820961. The reversal of 66820940 is 4902866.

It is a self number, because there is not a number n which added to its sum of digits gives 66820940.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 22109 + ... + 24948.

It is an arithmetic number, because the mean of its divisors is an integer number (5929308).

Almost surely, 2^66820940 is an apocalyptic number.

It is an amenable number.

66820940 is an abundant number, since it is smaller than the sum of its proper divisors (75482452).

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

66820940 is a wasteful number, since it uses less digits than its factorization.

66820940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47137 (or 47135 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 66820940 is about 8174.4076237976. The cubic root of 66820940 is about 405.7926659432.

The spelling of 66820940 in words is "sixty-six million, eight hundred twenty thousand, nine hundred forty".