66405306 has 64 divisors (see below), whose sum is σ = 151289856. Its totient is φ = 19252800.

The previous prime is 66405293. The next prime is 66405319. The reversal of 66405306 is 60350466.

It is an interprime number because it is at equal distance from previous prime (66405293) and next prime (66405319).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 173191 + ... + 173573.

It is an arithmetic number, because the mean of its divisors is an integer number (2363904).

Almost surely, 2^66405306 is an apocalyptic number.

66405306 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 66405306, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75644928).

66405306 is an abundant number, since it is smaller than the sum of its proper divisors (84884550).

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

66405306 is a wasteful number, since it uses less digits than its factorization.

66405306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507.

The product of its (nonzero) digits is 12960, while the sum is 30.

The square root of 66405306 is about 8148.9450851015. The cubic root of 66405306 is about 404.9495562841.

The spelling of 66405306 in words is "sixty-six million, four hundred five thousand, three hundred six".