65640307 has 4 divisors (see below), whose sum is σ = 69095080. Its totient is φ = 62185536.

The previous prime is 65640277. The next prime is 65640319. The reversal of 65640307 is 70304656.

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 65640307 - 2¹⁹ = 65116019 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65646307) 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 in 3 ways as a sum of consecutive naturals, for example, 1727358 + ... + 1727395.

It is an arithmetic number, because the mean of its divisors is an integer number (17273770).

Almost surely, 2^65640307 is an apocalyptic number.

65640307 is a deficient number, since it is larger than the sum of its proper divisors (3454773).

65640307 is a wasteful number, since it uses less digits than its factorization.

65640307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3454772.

The product of its (nonzero) digits is 15120, while the sum is 31.

The square root of 65640307 is about 8101.8705864757. The cubic root of 65640307 is about 403.3885200234.

The spelling of 65640307 in words is "sixty-five million, six hundred forty thousand, three hundred seven".