66021438708353 has 4 divisors (see below), whose sum is σ = 66022399382340. Its totient is φ = 66020478034368.

The previous prime is 66021438708307. The next prime is 66021438708361. The reversal of 66021438708353 is 35380783412066.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 31968530181184 + 34052908527169 = 5654072^2 + 5835487^2 .

It is a cyclic number.

It is not a de Polignac number, because 66021438708353 - 2⁸ = 66021438708097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66021438408353) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 480233900 + ... + 480371357.

It is an arithmetic number, because the mean of its divisors is an integer number (16505599845585).

Almost surely, 2^{66021438708353} is an apocalyptic number.

It is an amenable number.

66021438708353 is a deficient number, since it is larger than the sum of its proper divisors (960673987).

66021438708353 is an equidigital number, since it uses as much as digits as its factorization.

66021438708353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 960673986.

The product of its (nonzero) digits is 17418240, while the sum is 56.

The spelling of 66021438708353 in words is "sixty-six trillion, twenty-one billion, four hundred thirty-eight million, seven hundred eight thousand, three hundred fifty-three".