66831071 has 4 divisors (see below), whose sum is σ = 68986944. Its totient is φ = 64675200.

The previous prime is 66831053. The next prime is 66831143. The reversal of 66831071 is 17013866.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17013866 = 2 ⋅8506933.

It is a cyclic number.

It is not a de Polignac number, because 66831071 - 2⁶ = 66831007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66831001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1077890 + ... + 1077951.

It is an arithmetic number, because the mean of its divisors is an integer number (17246736).

Almost surely, 2^66831071 is an apocalyptic number.

66831071 is a deficient number, since it is larger than the sum of its proper divisors (2155873).

66831071 is a wasteful number, since it uses less digits than its factorization.

66831071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2155872.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 66831071 is about 8175.0272782420. The cubic root of 66831071 is about 405.8131728769.

The spelling of 66831071 in words is "sixty-six million, eight hundred thirty-one thousand, seventy-one".