66463865 has 16 divisors (see below), whose sum is σ = 86864400. Its totient is φ = 48525312.

The previous prime is 66463849. The next prime is 66463867. The reversal of 66463865 is 56836466.

It can be written as a sum of positive squares in 8 ways, for example, as 19855936 + 46607929 = 4456^2 + 6827^2 .

It is a cyclic number.

It is not a de Polignac number, because 66463865 - 2⁴ = 66463849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66463867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41 + ... + 11529.

It is an arithmetic number, because the mean of its divisors is an integer number (5429025).

Almost surely, 2^66463865 is an apocalyptic number.

66463865 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66463865 is a deficient number, since it is larger than the sum of its proper divisors (20400535).

66463865 is a wasteful number, since it uses less digits than its factorization.

66463865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11596.

The product of its digits is 622080, while the sum is 44.

The square root of 66463865 is about 8152.5373350878. The cubic root of 66463865 is about 405.0685551784.

The spelling of 66463865 in words is "sixty-six million, four hundred sixty-three thousand, eight hundred sixty-five".