66599520 has 144 divisors (see below), whose sum is σ = 227444112. Its totient is φ = 16373760.

The previous prime is 66599509. The next prime is 66599531. The reversal of 66599520 is 2599566.

66599520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (66599509) and next prime (66599531).

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 80710 + ... + 81530.

It is an arithmetic number, because the mean of its divisors is an integer number (1579473).

Almost surely, 2^66599520 is an apocalyptic number.

66599520 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 66599520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113722056).

66599520 is an abundant number, since it is smaller than the sum of its proper divisors (160844592).

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

66599520 is a wasteful number, since it uses less digits than its factorization.

66599520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 865 (or 844 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 42.

The square root of 66599520 is about 8160.8528966034. The cubic root of 66599520 is about 405.3439541115.

The spelling of 66599520 in words is "sixty-six million, five hundred ninety-nine thousand, five hundred twenty".