66899959 has 16 divisors (see below), whose sum is σ = 80363008. Its totient is φ = 54486432.

The previous prime is 66899951. The next prime is 66899983. The reversal of 66899959 is 95999866.

It is not a de Polignac number, because 66899959 - 2³ = 66899951 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66899897 and 66899906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66899951) 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, 8134 + ... + 14140.

It is an arithmetic number, because the mean of its divisors is an integer number (5022688).

Almost surely, 2^66899959 is an apocalyptic number.

66899959 is a deficient number, since it is larger than the sum of its proper divisors (13463049).

66899959 is a wasteful number, since it uses less digits than its factorization.

66899959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6094.

The product of its digits is 9447840, while the sum is 61.

The square root of 66899959 is about 8179.2395123263. The cubic root of 66899959 is about 405.9525594305.

The spelling of 66899959 in words is "sixty-six million, eight hundred ninety-nine thousand, nine hundred fifty-nine".