66871839 has 16 divisors (see below), whose sum is σ = 93133440. Its totient is φ = 42636960.

The previous prime is 66871801. The next prime is 66871843. The reversal of 66871839 is 93817866.

It is not a de Polignac number, because 66871839 - 2⁷ = 66871711 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66871859) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1444 + ... + 11654.

It is an arithmetic number, because the mean of its divisors is an integer number (5820840).

Almost surely, 2^66871839 is an apocalyptic number.

66871839 is a deficient number, since it is larger than the sum of its proper divisors (26261601).

66871839 is a wasteful number, since it uses less digits than its factorization.

66871839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10310.

The product of its digits is 435456, while the sum is 48.

The square root of 66871839 is about 8177.5203454348. The cubic root of 66871839 is about 405.8956735673.

The spelling of 66871839 in words is "sixty-six million, eight hundred seventy-one thousand, eight hundred thirty-nine".