640722300 has 144 divisors (see below), whose sum is σ = 1923626880. Its totient is φ = 164552960.

The previous prime is 640722263. The next prime is 640722323. The reversal of 640722300 is 3227046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 937759 + ... + 938441.

It is an arithmetic number, because the mean of its divisors is an integer number (13358520).

Almost surely, 2^640722300 is an apocalyptic number.

640722300 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 640722300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (961813440).

640722300 is an abundant number, since it is smaller than the sum of its proper divisors (1282904580).

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

640722300 is a wasteful number, since it uses less digits than its factorization.

640722300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812 (or 805 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 24.

The square root of 640722300 is about 25312.4929629620. The cubic root of 640722300 is about 862.0979516635.

Adding to 640722300 its reverse (3227046), we get a palindrome (643949346).

The spelling of 640722300 in words is "six hundred forty million, seven hundred twenty-two thousand, three hundred".