65999957 has 8 divisors (see below), whose sum is σ = 67172760. Its totient is φ = 64834560.

The previous prime is 65999951. The next prime is 65999993. The reversal of 65999957 is 75999956.

It can be written as a sum of positive squares in 4 ways, for example, as 5564881 + 60435076 = 2359^2 + 7774^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 65999957 - 2¹⁸ = 65737813 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 65999896 and 65999905.

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 7 ways as a sum of consecutive naturals, for example, 17957 + ... + 21317.

It is an arithmetic number, because the mean of its divisors is an integer number (8396595).

Almost surely, 2^65999957 is an apocalyptic number.

It is an amenable number.

65999957 is a deficient number, since it is larger than the sum of its proper divisors (1172803).

65999957 is a wasteful number, since it uses less digits than its factorization.

65999957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3703.

The product of its digits is 6889050, while the sum is 59.

The square root of 65999957 is about 8124.0357581685. The cubic root of 65999957 is about 404.1239142979.

Subtracting 65999957 from its reverse (75999956), we obtain a palindrome (9999999).

The spelling of 65999957 in words is "sixty-five million, nine hundred ninety-nine thousand, nine hundred fifty-seven".