66535968 has 48 divisors (see below), whose sum is σ = 175966560. Its totient is φ = 22012416.

The previous prime is 66535961. The next prime is 66535969. The reversal of 66535968 is 86953566.

It is a tau number, because it is divible by the number of its divisors (48).

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

It is not an unprimeable number, because it can be changed into a prime (66535961) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10623 + ... + 15681.

It is an arithmetic number, because the mean of its divisors is an integer number (3665970).

Almost surely, 2^66535968 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 66535968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87983280).

66535968 is an abundant number, since it is smaller than the sum of its proper divisors (109430592).

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

66535968 is a wasteful number, since it uses less digits than its factorization.

66535968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5209 (or 5201 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 48.

The square root of 66535968 is about 8156.9582566052. The cubic root of 66535968 is about 405.2149811239.

It can be divided in two parts, 6653 and 5968, that added together give a palindrome (12621).

The spelling of 66535968 in words is "sixty-six million, five hundred thirty-five thousand, nine hundred sixty-eight".