65821140 has 192 divisors, whose sum is σ = 255467520. Its totient is φ = 13668480.

The previous prime is 65821123. The next prime is 65821163. The reversal of 65821140 is 4112856.

65821140 is a `hidden beast` number, since 658 + 2 + 1 + 1 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 40789 + ... + 42371.

It is an arithmetic number, because the mean of its divisors is an integer number (1330560).

Almost surely, 2^65821140 is an apocalyptic number.

65821140 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 65821140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127733760).

65821140 is an abundant number, since it is smaller than the sum of its proper divisors (189646380).

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

65821140 is a wasteful number, since it uses less digits than its factorization.

65821140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1619 (or 1611 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 65821140 is about 8113.0228645062. The cubic root of 65821140 is about 403.7586131133.

Adding to 65821140 its reverse (4112856), we get a palindrome (69933996).

The spelling of 65821140 in words is "sixty-five million, eight hundred twenty-one thousand, one hundred forty".