65000021 has 2 divisors, whose sum is σ = 65000022. Its totient is φ = 65000020.

The previous prime is 65000011. The next prime is 65000029. The reversal of 65000021 is 12000056.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56415121 + 8584900 = 7511^2 + 2930^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65000021 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65000029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32500010 + 32500011.

It is an arithmetic number, because the mean of its divisors is an integer number (32500011).

Almost surely, 2^65000021 is an apocalyptic number.

It is an amenable number.

65000021 is a deficient number, since it is larger than the sum of its proper divisors (1).

65000021 is an equidigital number, since it uses as much as digits as its factorization.

65000021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 65000021 is about 8062.2590506632. The cubic root of 65000021 is about 402.0726191590.

Adding to 65000021 its reverse (12000056), we get a palindrome (77000077).

The spelling of 65000021 in words is "sixty-five million, twenty-one", and thus it is an aban number and an uban number.