65278791 has 12 divisors (see below), whose sum is σ = 97784232. Its totient is φ = 43519032.

The previous prime is 65278789. The next prime is 65278819. The reversal of 65278791 is 19787256.

65278791 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 65278791 - 2¹ = 65278789 is a prime.

It is a super-2 number, since 2×65278791² = 8522641108843362, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65276791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 134076 + ... + 134561.

It is an arithmetic number, because the mean of its divisors is an integer number (8148686).

Almost surely, 2^65278791 is an apocalyptic number.

65278791 is a deficient number, since it is larger than the sum of its proper divisors (32505441).

65278791 is an equidigital number, since it uses as much as digits as its factorization.

65278791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268652 (or 268640 counting only the distinct ones).

The product of its digits is 211680, while the sum is 45.

The square root of 65278791 is about 8079.5291323195. The cubic root of 65278791 is about 402.6465980921.

The spelling of 65278791 in words is "sixty-five million, two hundred seventy-eight thousand, seven hundred ninety-one".