64490000 has 50 divisors (see below), whose sum is σ = 156160950. Its totient is φ = 25792000.

The previous prime is 64489963. The next prime is 64490003. The reversal of 64490000 is 9446.

It can be written as a sum of positive squares in 5 ways, for example, as 8479744 + 56010256 = 2912^2 + 7484^2 .

It is a tau number, because it is divible by the number of its divisors (50).

It is not an unprimeable number, because it can be changed into a prime (64490003) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 6776 + ... + 13224.

It is an arithmetic number, because the mean of its divisors is an integer number (3123219).

Almost surely, 2^64490000 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 64490000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78080475).

64490000 is an abundant number, since it is smaller than the sum of its proper divisors (91670950).

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

64490000 is an equidigital number, since it uses as much as digits as its factorization.

64490000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6477 (or 6456 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 64490000 is about 8030.5666051655. The cubic root of 64490000 is about 401.0182391067.

Adding to 64490000 its reverse (9446), we get a palindrome (64499446).

It can be divided in two parts, 64 and 490000, that multiplied together give a square (31360000 = 5600²).

The spelling of 64490000 in words is "sixty-four million, four hundred ninety thousand".