66139090 has 16 divisors (see below), whose sum is σ = 119221272. Its totient is φ = 26417664.

The previous prime is 66139063. The next prime is 66139123. The reversal of 66139090 is 9093166.

It can be written as a sum of positive squares in 4 ways, for example, as 52809289 + 13329801 = 7267^2 + 3651^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3202 + ... + 11938.

Almost surely, 2^66139090 is an apocalyptic number.

66139090 is a deficient number, since it is larger than the sum of its proper divisors (53082182).

66139090 is a wasteful number, since it uses less digits than its factorization.

66139090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9501.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 66139090 is about 8132.5942970248. The cubic root of 66139090 is about 404.4076897783.

The spelling of 66139090 in words is "sixty-six million, one hundred thirty-nine thousand, ninety".