66021380 has 48 divisors (see below), whose sum is σ = 141571584. Its totient is φ = 25858560.

The previous prime is 66021367. The next prime is 66021391. The reversal of 66021380 is 8312066.

66021380 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 (26) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 295949 + ... + 296171.

It is an arithmetic number, because the mean of its divisors is an integer number (2949408).

Almost surely, 2^66021380 is an apocalyptic number.

It is an amenable number.

66021380 is an abundant number, since it is smaller than the sum of its proper divisors (75550204).

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

66021380 is a wasteful number, since it uses less digits than its factorization.

66021380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476 (or 474 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 66021380 is about 8125.3541461280. The cubic root of 66021380 is about 404.1676345792.

The spelling of 66021380 in words is "sixty-six million, twenty-one thousand, three hundred eighty".