641288940 has 96 divisors (see below), whose sum is σ = 1879320576. Its totient is φ = 163192320.

The previous prime is 641288939. The next prime is 641288941. The reversal of 641288940 is 49882146.

641288940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (641288939) and next prime (641288941).

It is a super-2 number, since 2×641288940² = 822503009132647200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 641288892 and 641288901.

It is not an unprimeable number, because it can be changed into a prime (641288941) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 133419 + ... + 138141.

It is an arithmetic number, because the mean of its divisors is an integer number (19576256).

Almost surely, 2^641288940 is an apocalyptic number.

641288940 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 641288940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (939660288).

641288940 is an abundant number, since it is smaller than the sum of its proper divisors (1238031636).

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

641288940 is a wasteful number, since it uses less digits than its factorization.

641288940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4839 (or 4837 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 42.

The square root of 641288940 is about 25323.6833813725. The cubic root of 641288940 is about 862.3520166192.

The spelling of 641288940 in words is "six hundred forty-one million, two hundred eighty-eight thousand, nine hundred forty".