66685696 has 144 divisors (see below), whose sum is σ = 176601600. Its totient is φ = 24330240.

The previous prime is 66685693. The next prime is 66685699. The reversal of 66685696 is 69658666.

It is an interprime number because it is at equal distance from previous prime (66685693) and next prime (66685699).

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (66685693) 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, 335005 + ... + 335203.

It is an arithmetic number, because the mean of its divisors is an integer number (1226400).

Almost surely, 2^66685696 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 66685696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88300800).

66685696 is an abundant number, since it is smaller than the sum of its proper divisors (109915904).

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

66685696 is a wasteful number, since it uses less digits than its factorization.

66685696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 236 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 52.

The square root of 66685696 is about 8166.1310300533. The cubic root of 66685696 is about 405.5187094511.

The spelling of 66685696 in words is "sixty-six million, six hundred eighty-five thousand, six hundred ninety-six".