641889392400 has 225 divisors, whose sum is σ = 2304207202693. Its totient is φ = 171132048000.

The previous prime is 641889392369. The next prime is 641889392471. The reversal of 641889392400 is 4293988146.

The square root of 641889392400 is 801180.

It is a perfect power (a square), and thus also a powerful number.

641889392400 is a `hidden beast` number, since 64 + 1 + 8 + 8 + 93 + 92 + 400 = 666.

641889392400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 231080181264 + 410809211136 = 480708^2 + 640944^2 .

It is a tau number, because it is divible by the number of its divisors (225).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 144210175 + ... + 144214625.

Almost surely, 2^641889392400 is an apocalyptic number.

641889392400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

641889392400 is the 801180-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 641889392400

641889392400 is an abundant number, since it is smaller than the sum of its proper divisors (1662317810293).

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

641889392400 is an frugal number, since it uses more digits than its factorization.

641889392400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8932 (or 4461 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

It can be divided in two parts, 641889 and 392400, that added together give a square (1034289 = 1017²).

The spelling of 641889392400 in words is "six hundred forty-one billion, eight hundred eighty-nine million, three hundred ninety-two thousand, four hundred".