65649240 has 144 divisors (see below), whose sum is σ = 227008080. Its totient is φ = 16450560.

The previous prime is 65649229. The next prime is 65649263. The reversal of 65649240 is 4294656.

65649240 is a `hidden beast` number, since 6 + 5 + 649 + 2 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 65649195 and 65649204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 103725 + ... + 104355.

It is an arithmetic number, because the mean of its divisors is an integer number (1576445).

Almost surely, 2^65649240 is an apocalyptic number.

65649240 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65649240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113504040).

65649240 is an abundant number, since it is smaller than the sum of its proper divisors (161358840).

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

65649240 is a wasteful number, since it uses less digits than its factorization.

65649240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 682 (or 658 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 65649240 is about 8102.4218601601. The cubic root of 65649240 is about 403.4068182630.

The spelling of 65649240 in words is "sixty-five million, six hundred forty-nine thousand, two hundred forty".