66961716 has 12 divisors (see below), whose sum is σ = 156244032. Its totient is φ = 22320568.

The previous prime is 66961693. The next prime is 66961799. The reversal of 66961716 is 61716966.

It is a tau number, because it is divible by the number of its divisors (12).

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, 2790060 + ... + 2790083.

It is an arithmetic number, because the mean of its divisors is an integer number (13020336).

Almost surely, 2^66961716 is an apocalyptic number.

It is an amenable number.

66961716 is an abundant number, since it is smaller than the sum of its proper divisors (89282316).

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

66961716 is a wasteful number, since it uses less digits than its factorization.

66961716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5580150 (or 5580148 counting only the distinct ones).

The product of its digits is 81648, while the sum is 42.

The square root of 66961716 is about 8183.0138702070. The cubic root of 66961716 is about 406.0774359485.

The spelling of 66961716 in words is "sixty-six million, nine hundred sixty-one thousand, seven hundred sixteen".