641006820 has 36 divisors (see below), whose sum is σ = 1944387900. Its totient is φ = 170935104.

The previous prime is 641006797. The next prime is 641006827. The reversal of 641006820 is 28600146.

It can be written as a sum of positive squares in 2 ways, for example, as 78747876 + 562258944 = 8874^2 + 23712^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (641006827) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1780395 + ... + 1780754.

It is an arithmetic number, because the mean of its divisors is an integer number (54010775).

Almost surely, 2^641006820 is an apocalyptic number.

641006820 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

641006820 is an abundant number, since it is smaller than the sum of its proper divisors (1303381080).

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

641006820 is a wasteful number, since it uses less digits than its factorization.

641006820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3561164 (or 3561159 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 641006820 is about 25318.1124888883. The cubic root of 641006820 is about 862.2255409021.

Adding to 641006820 its reverse (28600146), we get a palindrome (669606966).

The spelling of 641006820 in words is "six hundred forty-one million, six thousand, eight hundred twenty".