66289872 has 80 divisors (see below), whose sum is σ = 187987968. Its totient is φ = 19962240.

The previous prime is 66289871. The next prime is 66289877. The reversal of 66289872 is 27898266.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66289871) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 117463 + ... + 118025.

Almost surely, 2^66289872 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 66289872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93993984).

66289872 is an abundant number, since it is smaller than the sum of its proper divisors (121698096).

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

66289872 is a wasteful number, since it uses less digits than its factorization.

66289872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808 (or 802 counting only the distinct ones).

The product of its digits is 580608, while the sum is 48.

The square root of 66289872 is about 8141.8592471253. The cubic root of 66289872 is about 404.7147755511.

It can be divided in two parts, 66289 and 872, that added together give a triangular number (67161 = T₃₆₆).

The spelling of 66289872 in words is "sixty-six million, two hundred eighty-nine thousand, eight hundred seventy-two".