641309760 has 336 divisors, whose sum is σ = 2715987456. Its totient is φ = 135254016.

The previous prime is 641309749. The next prime is 641309761. The reversal of 641309760 is 67903146.

641309760 is a `hidden beast` number, since 641 + 3 + 0 + 9 + 7 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a super-2 number, since 2×641309760² = 822556416542515200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (641309761) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 260857 + ... + 263303.

It is an arithmetic number, because the mean of its divisors is an integer number (8083296).

Almost surely, 2^641309760 is an apocalyptic number.

641309760 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 641309760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1357993728).

641309760 is an abundant number, since it is smaller than the sum of its proper divisors (2074677696).

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

641309760 is a wasteful number, since it uses less digits than its factorization.

641309760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2490 (or 2477 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 641309760 is about 25324.0944556760. The cubic root of 641309760 is about 862.3613488529.

The spelling of 641309760 in words is "six hundred forty-one million, three hundred nine thousand, seven hundred sixty".