641120400 has 480 divisors, whose sum is σ = 2490912000. Its totient is φ = 156119040.

The previous prime is 641120357. The next prime is 641120503. The reversal of 641120400 is 4021146.

641120400 is a `hidden beast` number, since 641 + 1 + 20 + 4 + 0 + 0 = 666.

It is a super-2 number, since 2×641120400² = 822070734592320000, which contains 22 as substring.

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 (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7203556 + ... + 7203644.

It is an arithmetic number, because the mean of its divisors is an integer number (5189400).

Almost surely, 2^641120400 is an apocalyptic number.

641120400 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 641120400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1245456000).

641120400 is an abundant number, since it is smaller than the sum of its proper divisors (1849791600).

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

641120400 is a wasteful number, since it uses less digits than its factorization.

641120400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 641120400 is about 25320.3554477420. The cubic root of 641120400 is about 862.2764638097.

Adding to 641120400 its reverse (4021146), we get a palindrome (645141546).

The spelling of 641120400 in words is "six hundred forty-one million, one hundred twenty thousand, four hundred".