66633385 has 24 divisors (see below), whose sum is σ = 100174536. Its totient is φ = 42174720.

The previous prime is 66633379. The next prime is 66633389. The reversal of 66633385 is 58333666.

It can be written as a sum of positive squares in 4 ways, for example, as 3732624 + 62900761 = 1932^2 + 7931^2 .

It is not a de Polignac number, because 66633385 - 2³ = 66633377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66633389) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 7276 + ... + 13645.

It is an arithmetic number, because the mean of its divisors is an integer number (4173939).

Almost surely, 2^66633385 is an apocalyptic number.

66633385 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66633385 is a deficient number, since it is larger than the sum of its proper divisors (33541151).

66633385 is a wasteful number, since it uses less digits than its factorization.

66633385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20953 (or 20946 counting only the distinct ones).

The product of its digits is 233280, while the sum is 40.

The square root of 66633385 is about 8162.9274773209. The cubic root of 66633385 is about 405.4126465335.

The spelling of 66633385 in words is "sixty-six million, six hundred thirty-three thousand, three hundred eighty-five".