65999897 has 4 divisors (see below), whose sum is σ = 67783716. Its totient is φ = 64216080.

The previous prime is 65999821. The next prime is 65999909. The reversal of 65999897 is 79899956.

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

It can be written as a sum of positive squares in 2 ways, for example, as 63027721 + 2972176 = 7939^2 + 1724^2 .

It is a cyclic number.

It is not a de Polignac number, because 65999897 - 2¹⁴ = 65983513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65999807) 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, 891854 + ... + 891927.

It is an arithmetic number, because the mean of its divisors is an integer number (16945929).

Almost surely, 2^65999897 is an apocalyptic number.

It is an amenable number.

65999897 is a deficient number, since it is larger than the sum of its proper divisors (1783819).

65999897 is a wasteful number, since it uses less digits than its factorization.

65999897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1783818.

The product of its digits is 11022480, while the sum is 62.

The square root of 65999897 is about 8124.0320654217. The cubic root of 65999897 is about 404.1237918360.

The spelling of 65999897 in words is "sixty-five million, nine hundred ninety-nine thousand, eight hundred ninety-seven".