65440540 has 24 divisors (see below), whose sum is σ = 149918832. Its totient is φ = 23796480.

The previous prime is 65440517. The next prime is 65440547. The reversal of 65440540 is 4504456.

It is a junction number, because it is equal to n+sod(n) for n = 65440499 and 65440508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65440547) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 148509 + ... + 148948.

It is an arithmetic number, because the mean of its divisors is an integer number (6246618).

Almost surely, 2^65440540 is an apocalyptic number.

It is an amenable number.

65440540 is an abundant number, since it is smaller than the sum of its proper divisors (84478292).

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

65440540 is a wasteful number, since it uses less digits than its factorization.

65440540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297477 (or 297475 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 28.

The square root of 65440540 is about 8089.5327429957. The cubic root of 65440540 is about 402.9788855318.

Adding to 65440540 its reverse (4504456), we get a palindrome (69944996).

The spelling of 65440540 in words is "sixty-five million, four hundred forty thousand, five hundred forty".