65115540 has 72 divisors (see below), whose sum is σ = 225738240. Its totient is φ = 14883264.

The previous prime is 65115521. The next prime is 65115541. The reversal of 65115540 is 4551156.

It is a happy number.

65115540 is a `hidden beast` number, since 6 + 5 + 115 + 540 = 666.

65115540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65115541) 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 23 ways as a sum of consecutive naturals, for example, 24580 + ... + 27099.

Almost surely, 2^65115540 is an apocalyptic number.

65115540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65115540 is an abundant number, since it is smaller than the sum of its proper divisors (160622700).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65115540 is a wasteful number, since it uses less digits than its factorization.

65115540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51701 (or 51696 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The square root of 65115540 is about 8069.4200535107. The cubic root of 65115540 is about 402.3106679979.

Adding to 65115540 its reverse (4551156), we get a palindrome (69666696).

The spelling of 65115540 in words is "sixty-five million, one hundred fifteen thousand, five hundred forty".