641144020 has 48 divisors (see below), whose sum is σ = 1478736000. Its totient is φ = 231566720.

The previous prime is 641144011. The next prime is 641144027. The reversal of 641144020 is 20441146.

It is a super-2 number, since 2×641144020² = 822131308763520800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 641143982 and 641144000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641144027) 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, 23001 + ... + 42559.

It is an arithmetic number, because the mean of its divisors is an integer number (30807000).

Almost surely, 2^641144020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641144020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (739368000).

641144020 is an abundant number, since it is smaller than the sum of its proper divisors (837591980).

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

641144020 is a wasteful number, since it uses less digits than its factorization.

641144020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19728 (or 19726 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 641144020 is about 25320.8218665982. The cubic root of 641144020 is about 862.2870529388.

Adding to 641144020 its reverse (20441146), we get a palindrome (661585166).

The spelling of 641144020 in words is "six hundred forty-one million, one hundred forty-four thousand, twenty".