65616240 has 80 divisors (see below), whose sum is σ = 212272128. Its totient is φ = 16735488.

The previous prime is 65616211. The next prime is 65616247. The reversal of 65616240 is 4261656.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 65616198 and 65616207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65616247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 424 + ... + 11463.

Almost surely, 2^65616240 is an apocalyptic number.

65616240 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 65616240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106136064).

65616240 is an abundant number, since it is smaller than the sum of its proper divisors (146655888).

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

65616240 is a wasteful number, since it uses less digits than its factorization.

65616240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11926 (or 11920 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 65616240 is about 8100.3851760271. The cubic root of 65616240 is about 403.3392132346.

Adding to 65616240 its reverse (4261656), we get a palindrome (69877896).

It can be divided in two parts, 65616 and 240, that added together give a palindrome (65856).

The spelling of 65616240 in words is "sixty-five million, six hundred sixteen thousand, two hundred forty".