66845856 has 96 divisors (see below), whose sum is σ = 218792448. Its totient is φ = 17360640.

The previous prime is 66845839. The next prime is 66845903. The reversal of 66845856 is 65854866.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2871 + ... + 11913.

It is an arithmetic number, because the mean of its divisors is an integer number (2279088).

Almost surely, 2^66845856 is an apocalyptic number.

66845856 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66845856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109396224).

66845856 is an abundant number, since it is smaller than the sum of its proper divisors (151946592).

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

66845856 is a wasteful number, since it uses less digits than its factorization.

66845856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9074 (or 9066 counting only the distinct ones).

The product of its digits is 1382400, while the sum is 48.

The square root of 66845856 is about 8175.9315065624. The cubic root of 66845856 is about 405.8430966098.

The spelling of 66845856 in words is "sixty-six million, eight hundred forty-five thousand, eight hundred fifty-six".