66031880 has 32 divisors (see below), whose sum is σ = 148881240. Its totient is φ = 26357760.

The previous prime is 66031879. The next prime is 66031907. The reversal of 66031880 is 8813066.

66031880 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 65577604 + 454276 = 8098^2 + 674^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21650 + ... + 24510.

Almost surely, 2^66031880 is an apocalyptic number.

It is an amenable number.

66031880 is an abundant number, since it is smaller than the sum of its proper divisors (82849360).

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

66031880 is a wasteful number, since it uses less digits than its factorization.

66031880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3449 (or 3445 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 66031880 is about 8126.0002461236. Note that the first 3 decimals coincide. The cubic root of 66031880 is about 404.1890596348.

The spelling of 66031880 in words is "sixty-six million, thirty-one thousand, eight hundred eighty".