66210438 has 32 divisors (see below), whose sum is σ = 151718400. Its totient is φ = 18869760.

The previous prime is 66210407. The next prime is 66210439. The reversal of 66210438 is 83401266.

66210438 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66210439) 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 15 ways as a sum of consecutive naturals, for example, 17103 + ... + 20613.

It is an arithmetic number, because the mean of its divisors is an integer number (4741200).

Almost surely, 2^66210438 is an apocalyptic number.

66210438 is an abundant number, since it is smaller than the sum of its proper divisors (85507962).

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

66210438 is a wasteful number, since it uses less digits than its factorization.

66210438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3972.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 66210438 is about 8136.9796607832. The cubic root of 66210438 is about 404.5530567148.

The spelling of 66210438 in words is "sixty-six million, two hundred ten thousand, four hundred thirty-eight".