66835920 has 80 divisors (see below), whose sum is σ = 218111040. Its totient is φ = 16883712.

The previous prime is 66835919. The next prime is 66835933. The reversal of 66835920 is 2953866.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

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, 2769 + ... + 11888.

It is an arithmetic number, because the mean of its divisors is an integer number (2726388).

Almost surely, 2^66835920 is an apocalyptic number.

66835920 is a gapful number since it is divisible by the number (60) 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 66835920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109055520).

66835920 is an abundant number, since it is smaller than the sum of its proper divisors (151275120).

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

66835920 is a wasteful number, since it uses less digits than its factorization.

66835920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14692 (or 14686 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 39.

The square root of 66835920 is about 8175.3238467965. The cubic root of 66835920 is about 405.8229873761.

The spelling of 66835920 in words is "sixty-six million, eight hundred thirty-five thousand, nine hundred twenty".