66015872 has 64 divisors (see below), whose sum is σ = 143442600. Its totient is φ = 30081024.

The previous prime is 66015869. The next prime is 66015883. The reversal of 66015872 is 27851066.

66015872 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 4 ways, for example, as 57395776 + 8620096 = 7576^2 + 2936^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a hoax number, since the sum of its digits (35) coincides with the sum of the digits of its distinct prime factors.

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 7 ways as a sum of consecutive naturals, for example, 161204 + ... + 161612.

Almost surely, 2^66015872 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66015872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71721300).

66015872 is an abundant number, since it is smaller than the sum of its proper divisors (77426728).

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

66015872 is a wasteful number, since it uses less digits than its factorization.

66015872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533 (or 521 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 66015872 is about 8125.0151999858. The cubic root of 66015872 is about 404.1563946988.

The spelling of 66015872 in words is "sixty-six million, fifteen thousand, eight hundred seventy-two".