641632500 has 90 divisors (see below), whose sum is σ = 2026802778. Its totient is φ = 171096000.

The previous prime is 641632499. The next prime is 641632501. The reversal of 641632500 is 5236146.

641632500 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 (641632499) and next prime (641632501).

It can be written as a sum of positive squares in 5 ways, for example, as 130782096 + 510850404 = 11436^2 + 22602^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641632501) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 8242 + ... + 36758.

Almost surely, 2^641632500 is an apocalyptic number.

641632500 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 641632500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1013401389).

641632500 is an abundant number, since it is smaller than the sum of its proper divisors (1385170278).

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

641632500 is a wasteful number, since it uses less digits than its factorization.

641632500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28547 (or 28527 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 641632500 is about 25330.4658464861. The cubic root of 641632500 is about 862.5059860958.

Adding to 641632500 its reverse (5236146), we get a palindrome (646868646).

The spelling of 641632500 in words is "six hundred forty-one million, six hundred thirty-two thousand, five hundred".