65243840 has 56 divisors (see below), whose sum is σ = 160397952. Its totient is φ = 25251840.

The previous prime is 65243821. The next prime is 65243861. The reversal of 65243840 is 4834256.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 65243797 and 65243806.

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, 6632 + ... + 13208.

Almost surely, 2^65243840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65243840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80198976).

65243840 is an abundant number, since it is smaller than the sum of its proper divisors (95154112).

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

65243840 is a wasteful number, since it uses less digits than its factorization.

65243840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6625 (or 6615 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 32.

The square root of 65243840 is about 8077.3659072745. The cubic root of 65243840 is about 402.5747247553.

The spelling of 65243840 in words is "sixty-five million, two hundred forty-three thousand, eight hundred forty".