66006720 has 336 divisors, whose sum is σ = 256288032. Its totient is φ = 15482880.

The previous prime is 66006713. The next prime is 66006727. The reversal of 66006720 is 2760066.

66006720 = T₃₂₅ + T₃₂₆ + ... + T₇₅₄.

It is an interprime number because it is at equal distance from previous prime (66006713) and next prime (66006727).

It is not an unprimeable number, because it can be changed into a prime (66006727) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1535019 + ... + 1535061.

It is an arithmetic number, because the mean of its divisors is an integer number (762762).

Almost surely, 2^66006720 is an apocalyptic number.

66006720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66006720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128144016).

66006720 is an abundant number, since it is smaller than the sum of its proper divisors (190281312).

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

66006720 is a wasteful number, since it uses less digits than its factorization.

66006720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 66006720 is about 8124.4519815185. The cubic root of 66006720 is about 404.1377173204.

Adding to 66006720 its reverse (2760066), we get a palindrome (68766786).

The spelling of 66006720 in words is "sixty-six million, six thousand, seven hundred twenty".