66839473 has 4 divisors (see below), whose sum is σ = 70357360. Its totient is φ = 63321588.

The previous prime is 66839467. The next prime is 66839483. The reversal of 66839473 is 37493866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 37493866 = 2 ⋅18746933.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66839473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66839483) 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, 1758915 + ... + 1758952.

It is an arithmetic number, because the mean of its divisors is an integer number (17589340).

Almost surely, 2^66839473 is an apocalyptic number.

It is an amenable number.

66839473 is a deficient number, since it is larger than the sum of its proper divisors (3517887).

66839473 is a wasteful number, since it uses less digits than its factorization.

66839473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3517886.

The product of its digits is 653184, while the sum is 46.

The square root of 66839473 is about 8175.5411441690. The cubic root of 66839473 is about 405.8301784371.

The spelling of 66839473 in words is "sixty-six million, eight hundred thirty-nine thousand, four hundred seventy-three".