66878090 has 8 divisors (see below), whose sum is σ = 120380580. Its totient is φ = 26751232.

The previous prime is 66878083. The next prime is 66878099. The reversal of 66878090 is 9087866.

It can be written as a sum of positive squares in 2 ways, for example, as 66080641 + 797449 = 8129^2 + 893^2 .

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 (66878099) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3343895 + ... + 3343914.

Almost surely, 2^66878090 is an apocalyptic number.

66878090 is a deficient number, since it is larger than the sum of its proper divisors (53502490).

66878090 is a wasteful number, since it uses less digits than its factorization.

66878090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6687816.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 66878090 is about 8177.9025428284. The cubic root of 66878090 is about 405.9083205192.

The spelling of 66878090 in words is "sixty-six million, eight hundred seventy-eight thousand, ninety".