66920980 has 96 divisors (see below), whose sum is σ = 169827840. Its totient is φ = 21665280.

The previous prime is 66920977. The next prime is 66920981. The reversal of 66920980 is 8902966.

It is a happy number.

66920980 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66920981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 215025 + ... + 215335.

It is an arithmetic number, because the mean of its divisors is an integer number (1769040).

Almost surely, 2^66920980 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66920980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84913920).

66920980 is an abundant number, since it is smaller than the sum of its proper divisors (102906860).

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

66920980 is a wasteful number, since it uses less digits than its factorization.

66920980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 66920980 is about 8180.5244330666. The cubic root of 66920980 is about 405.9950738319.

The spelling of 66920980 in words is "sixty-six million, nine hundred twenty thousand, nine hundred eighty".