65140639 has 4 divisors (see below), whose sum is σ = 65363256. Its totient is φ = 64918024.

The previous prime is 65140631. The next prime is 65140643. The reversal of 65140639 is 93604156.

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 65140639 - 2³ = 65140631 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65140631) 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, 110869 + ... + 111454.

It is an arithmetic number, because the mean of its divisors is an integer number (16340814).

Almost surely, 2^65140639 is an apocalyptic number.

65140639 is a deficient number, since it is larger than the sum of its proper divisors (222617).

65140639 is a wasteful number, since it uses less digits than its factorization.

65140639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222616.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 65140639 is about 8070.9750959844. The cubic root of 65140639 is about 402.3623520166.

The spelling of 65140639 in words is "sixty-five million, one hundred forty thousand, six hundred thirty-nine".