641700400 has 240 divisors, whose sum is σ = 1793456640. Its totient is φ = 218444800.

The previous prime is 641700379. The next prime is 641700401. The reversal of 641700400 is 4007146.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (641700401) 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, 5997147 + ... + 5997253.

It is an arithmetic number, because the mean of its divisors is an integer number (7472736).

Almost surely, 2^641700400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641700400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (896728320).

641700400 is an abundant number, since it is smaller than the sum of its proper divisors (1151756240).

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

641700400 is a wasteful number, since it uses less digits than its factorization.

641700400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212 (or 201 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 641700400 is about 25331.8060943155. The cubic root of 641700400 is about 862.5364095811.

Adding to 641700400 its reverse (4007146), we get a palindrome (645707546).

The spelling of 641700400 in words is "six hundred forty-one million, seven hundred thousand, four hundred".