66271538 has 4 divisors (see below), whose sum is σ = 99407310. Its totient is φ = 33135768.

The previous prime is 66271537. The next prime is 66271547. The reversal of 66271538 is 83517266.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 63952009 + 2319529 = 7997^2 + 1523^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66271537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16567883 + ... + 16567886.

Almost surely, 2^66271538 is an apocalyptic number.

66271538 is a deficient number, since it is larger than the sum of its proper divisors (33135772).

66271538 is a wasteful number, since it uses less digits than its factorization.

66271538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33135771.

The product of its digits is 60480, while the sum is 38.

The square root of 66271538 is about 8140.7332593569. The cubic root of 66271538 is about 404.6774610281.

The spelling of 66271538 in words is "sixty-six million, two hundred seventy-one thousand, five hundred thirty-eight".