65999959 has 4 divisors (see below), whose sum is σ = 66238504. Its totient is φ = 65761416.

The previous prime is 65999951. The next prime is 65999993. The reversal of 65999959 is 95999956.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 65999959 - 2³ = 65999951 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 65999897 and 65999906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65999951) 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, 118857 + ... + 119410.

It is an arithmetic number, because the mean of its divisors is an integer number (16559626).

Almost surely, 2^65999959 is an apocalyptic number.

65999959 is a deficient number, since it is larger than the sum of its proper divisors (238545).

65999959 is a wasteful number, since it uses less digits than its factorization.

65999959 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238544.

The product of its digits is 8857350, while the sum is 61.

The square root of 65999959 is about 8124.0358812600. The cubic root of 65999959 is about 404.1239183800.

The spelling of 65999959 in words is "sixty-five million, nine hundred ninety-nine thousand, nine hundred fifty-nine".