66839859 has 6 divisors (see below), whose sum is σ = 96546476. Its totient is φ = 44559900.

The previous prime is 66839849. The next prime is 66839873. The reversal of 66839859 is 95893866.

It is not a de Polignac number, because 66839859 - 2⁵ = 66839827 is a prime.

It is a super-2 number, since 2×66839859² = 8935133502279762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66839819) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3713317 + ... + 3713334.

Almost surely, 2^66839859 is an apocalyptic number.

66839859 is a deficient number, since it is larger than the sum of its proper divisors (29706617).

66839859 is a wasteful number, since it uses less digits than its factorization.

66839859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7426657 (or 7426654 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The square root of 66839859 is about 8175.5647511349. The cubic root of 66839859 is about 405.8309596628.

The spelling of 66839859 in words is "sixty-six million, eight hundred thirty-nine thousand, eight hundred fifty-nine".