65615540 has 24 divisors (see below), whose sum is σ = 138711552. Its totient is φ = 26071200.

The previous prime is 65615533. The next prime is 65615551. The reversal of 65615540 is 4551656.

It is a junction number, because it is equal to n+sod(n) for n = 65615497 and 65615506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7844 + ... + 13883.

It is an arithmetic number, because the mean of its divisors is an integer number (5779648).

Almost surely, 2^65615540 is an apocalyptic number.

It is an amenable number.

65615540 is an abundant number, since it is smaller than the sum of its proper divisors (73096012).

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

65615540 is a wasteful number, since it uses less digits than its factorization.

65615540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21887 (or 21885 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 32.

The square root of 65615540 is about 8100.3419680900. The cubic root of 65615540 is about 403.3377789430.

The spelling of 65615540 in words is "sixty-five million, six hundred fifteen thousand, five hundred forty".