66271939 has 4 divisors (see below), whose sum is σ = 66293656. Its totient is φ = 66250224.

The previous prime is 66271903. The next prime is 66271963. The reversal of 66271939 is 93917266.

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

It is a cyclic number.

It is not a de Polignac number, because 66271939 - 2¹⁹ = 65747651 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66271895 and 66271904.

It is not an unprimeable number, because it can be changed into a prime (66271979) 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, 5349 + ... + 12694.

It is an arithmetic number, because the mean of its divisors is an integer number (16573414).

Almost surely, 2^66271939 is an apocalyptic number.

66271939 is a deficient number, since it is larger than the sum of its proper divisors (21717).

66271939 is a wasteful number, since it uses less digits than its factorization.

66271939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21716.

The product of its digits is 122472, while the sum is 43.

The square root of 66271939 is about 8140.7578885507. The cubic root of 66271939 is about 404.6782772424.

The spelling of 66271939 in words is "sixty-six million, two hundred seventy-one thousand, nine hundred thirty-nine".