65120400 has 90 divisors (see below), whose sum is σ = 225998370. Its totient is φ = 17364480.

The previous prime is 65120371. The next prime is 65120417. The reversal of 65120400 is 402156.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 14653584 + 50466816 = 3828^2 + 7104^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 5445 + ... + 12644.

It is an arithmetic number, because the mean of its divisors is an integer number (2511093).

Almost surely, 2^65120400 is an apocalyptic number.

65120400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65120400 is an abundant number, since it is smaller than the sum of its proper divisors (160877970).

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

65120400 is a wasteful number, since it uses less digits than its factorization.

65120400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18113 (or 18099 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 65120400 is about 8069.7211847746. The cubic root of 65120400 is about 402.3206767772.

Adding to 65120400 its reverse (402156), we get a palindrome (65522556).

The spelling of 65120400 in words is "sixty-five million, one hundred twenty thousand, four hundred".