66311890 has 8 divisors (see below), whose sum is σ = 119361420. Its totient is φ = 26524752.

The previous prime is 66311879. The next prime is 66311897. The reversal of 66311890 is 9811366.

It can be written as a sum of positive squares in 2 ways, for example, as 63377521 + 2934369 = 7961^2 + 1713^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (66311897) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3315585 + ... + 3315604.

Almost surely, 2^66311890 is an apocalyptic number.

66311890 is a deficient number, since it is larger than the sum of its proper divisors (53049530).

66311890 is a wasteful number, since it uses less digits than its factorization.

66311890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6631196.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 66311890 is about 8143.2112830259. The cubic root of 66311890 is about 404.7595788936.

The spelling of 66311890 in words is "sixty-six million, three hundred eleven thousand, eight hundred ninety".