65144509 has 2 divisors, whose sum is σ = 65144510. Its totient is φ = 65144508.

The previous prime is 65144507. The next prime is 65144539. The reversal of 65144509 is 90544156.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43956900 + 21187609 = 6630^2 + 4603^2 .

It is a cyclic number.

It is not a de Polignac number, because 65144509 - 2¹ = 65144507 is a prime.

Together with 65144507, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65144503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32572254 + 32572255.

It is an arithmetic number, because the mean of its divisors is an integer number (32572255).

Almost surely, 2^65144509 is an apocalyptic number.

It is an amenable number.

65144509 is a deficient number, since it is larger than the sum of its proper divisors (1).

65144509 is an equidigital number, since it uses as much as digits as its factorization.

65144509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 65144509 is about 8071.2148404066. The cubic root of 65144509 is about 402.3703199635.

It can be divided in two parts, 65144 and 509, that multiplied together give a triangular number (33158296 = T₈₁₄₃).

The spelling of 65144509 in words is "sixty-five million, one hundred forty-four thousand, five hundred nine".