66631120 has 20 divisors (see below), whose sum is σ = 154917540. Its totient is φ = 26652416.

The previous prime is 66631099. The next prime is 66631133. The reversal of 66631120 is 2113666.

It can be written as a sum of positive squares in 2 ways, for example, as 9960336 + 56670784 = 3156^2 + 7528^2 .

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, 416365 + ... + 416524.

It is an arithmetic number, because the mean of its divisors is an integer number (7745877).

Almost surely, 2^66631120 is an apocalyptic number.

It is an amenable number.

66631120 is an abundant number, since it is smaller than the sum of its proper divisors (88286420).

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

66631120 is a wasteful number, since it uses less digits than its factorization.

66631120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 832902 (or 832896 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 66631120 is about 8162.7887391504. The cubic root of 66631120 is about 405.4080528900.

Adding to 66631120 its reverse (2113666), we get a palindrome (68744786).

The spelling of 66631120 in words is "sixty-six million, six hundred thirty-one thousand, one hundred twenty".