64720400 has 60 divisors (see below), whose sum is σ = 159729732. Its totient is φ = 25182720.

The previous prime is 64720393. The next prime is 64720417. The reversal of 64720400 is 402746.

64720400 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 6 ways, for example, as 976144 + 63744256 = 988^2 + 7984^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12614 + ... + 16986.

Almost surely, 2^64720400 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 64720400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79864866).

64720400 is an abundant number, since it is smaller than the sum of its proper divisors (95009332).

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

64720400 is a wasteful number, since it uses less digits than its factorization.

64720400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4428 (or 4417 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 64720400 is about 8044.8990049596. The cubic root of 64720400 is about 401.4952370344.

The spelling of 64720400 in words is "sixty-four million, seven hundred twenty thousand, four hundred".