65521320 has 64 divisors (see below), whose sum is σ = 199808640. Its totient is φ = 17184000.

The previous prime is 65521307. The next prime is 65521327. The reversal of 65521320 is 2312556.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (65521327) 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, 2845 + ... + 11795.

It is an arithmetic number, because the mean of its divisors is an integer number (3122010).

Almost surely, 2^65521320 is an apocalyptic number.

65521320 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 65521320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99904320).

65521320 is an abundant number, since it is smaller than the sum of its proper divisors (134287320).

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

65521320 is a wasteful number, since it uses less digits than its factorization.

65521320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9026 (or 9022 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 65521320 is about 8094.5240749534. The cubic root of 65521320 is about 403.1446301360.

Adding to 65521320 its reverse (2312556), we get a palindrome (67833876).

The spelling of 65521320 in words is "sixty-five million, five hundred twenty-one thousand, three hundred twenty".