65399999 has 4 divisors (see below), whose sum is σ = 74742864. Its totient is φ = 56057136.

The previous prime is 65399989. The next prime is 65400007. The reversal of 65399999 is 99999356.

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 65399999 - 2⁸ = 65399743 is a prime.

65399999 is a modest number, since divided by 9999 gives 6539 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65399989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4671422 + ... + 4671435.

It is an arithmetic number, because the mean of its divisors is an integer number (18685716).

Almost surely, 2^65399999 is an apocalyptic number.

65399999 is a deficient number, since it is larger than the sum of its proper divisors (9342865).

65399999 is an equidigital number, since it uses as much as digits as its factorization.

65399999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9342864.

The product of its digits is 5314410, while the sum is 59.

The square root of 65399999 is about 8087.0265858349. The cubic root of 65399999 is about 402.8956519999.

The spelling of 65399999 in words is "sixty-five million, three hundred ninety-nine thousand, nine hundred ninety-nine".