641520000 has 560 divisors, whose sum is σ = 2612116980. Its totient is φ = 155520000.

The previous prime is 641519999. The next prime is 641520017. The reversal of 641520000 is 25146.

It is a happy number.

641520000 is a `hidden beast` number, since 641 + 5 + 20 + 0 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 69 ways as a sum of consecutive naturals, for example, 58319995 + ... + 58320005.

Almost surely, 2^641520000 is an apocalyptic number.

641520000 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 641520000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1306058490).

641520000 is an abundant number, since it is smaller than the sum of its proper divisors (1970596980).

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

641520000 is an frugal number, since it uses more digits than its factorization.

641520000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63 (or 21 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 641520000 is about 25328.2451030465. The cubic root of 641520000 is about 862.4555742713.

Adding to 641520000 its reverse (25146), we get a palindrome (641545146).

The spelling of 641520000 in words is "six hundred forty-one million, five hundred twenty thousand".