66705672 has 64 divisors (see below), whose sum is σ = 186868800. Its totient is φ = 19664640.

The previous prime is 66705659. The next prime is 66705673. The reversal of 66705672 is 27650766.

It is a self number, because there is not a number n which added to its sum of digits gives 66705672.

It is not an unprimeable number, because it can be changed into a prime (66705673) 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, 6354 + ... + 13182.

It is an arithmetic number, because the mean of its divisors is an integer number (2919825).

Almost surely, 2^66705672 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 66705672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93434400).

66705672 is an abundant number, since it is smaller than the sum of its proper divisors (120163128).

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

66705672 is a wasteful number, since it uses less digits than its factorization.

66705672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6886 (or 6882 counting only the distinct ones).

The product of its (nonzero) digits is 105840, while the sum is 39.

The square root of 66705672 is about 8167.3540390998. The cubic root of 66705672 is about 405.5591970594.

The spelling of 66705672 in words is "sixty-six million, seven hundred five thousand, six hundred seventy-two".