66491120 has 20 divisors (see below), whose sum is σ = 154592040. Its totient is φ = 26596416.

The previous prime is 66491107. The next prime is 66491147. The reversal of 66491120 is 2119466.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 415490 + ... + 415649.

It is an arithmetic number, because the mean of its divisors is an integer number (7729602).

Almost surely, 2^66491120 is an apocalyptic number.

It is an amenable number.

66491120 is an abundant number, since it is smaller than the sum of its proper divisors (88100920).

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

66491120 is a wasteful number, since it uses less digits than its factorization.

66491120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 831152 (or 831146 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 66491120 is about 8154.2087292392. The cubic root of 66491120 is about 405.1239167634.

The spelling of 66491120 in words is "sixty-six million, four hundred ninety-one thousand, one hundred twenty".