66638466 has 24 divisors (see below), whose sum is σ = 145012140. Its totient is φ = 22116096.

The previous prime is 66638449. The next prime is 66638471. The reversal of 66638466 is 66483666.

66638466 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 60512841 + 6125625 = 7779^2 + 2475^2 .

It is a super-3 number, since 3×66638466³ (a number of 24 digits) contains 333 as substring.

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 11 ways as a sum of consecutive naturals, for example, 3751 + ... + 12138.

Almost surely, 2^66638466 is an apocalyptic number.

66638466 is an abundant number, since it is smaller than the sum of its proper divisors (78373674).

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

66638466 is a wasteful number, since it uses less digits than its factorization.

66638466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16130 (or 16127 counting only the distinct ones).

The product of its digits is 746496, while the sum is 45.

The square root of 66638466 is about 8163.2386955179. The cubic root of 66638466 is about 405.4229509242.

It can be divided in two parts, 6663 and 8466, that added together give a square (15129 = 123²).

The spelling of 66638466 in words is "sixty-six million, six hundred thirty-eight thousand, four hundred sixty-six".