64684728 has 96 divisors (see below), whose sum is σ = 189961200. Its totient is φ = 19805184.

The previous prime is 64684727. The next prime is 64684729. The reversal of 64684728 is 82748646.

64684728 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (64684727) and next prime (64684729).

It is a super-2 number, since 2×64684728² = 8368228072867968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64684723) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 52018 + ... + 53246.

Almost surely, 2^64684728 is an apocalyptic number.

64684728 is a gapful number since it is divisible by the number (68) 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 64684728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94980600).

64684728 is an abundant number, since it is smaller than the sum of its proper divisors (125276472).

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

64684728 is a wasteful number, since it uses less digits than its factorization.

64684728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1301 (or 1294 counting only the distinct ones).

The product of its digits is 516096, while the sum is 45.

The square root of 64684728 is about 8042.6816423380. The cubic root of 64684728 is about 401.4214593166.

The spelling of 64684728 in words is "sixty-four million, six hundred eighty-four thousand, seven hundred twenty-eight".