64661280 has 96 divisors (see below), whose sum is σ = 212575104. Its totient is φ = 16490496.

The previous prime is 64661279. The next prime is 64661299. The reversal of 64661280 is 8216646.

It is a happy number.

64661280 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×64661280² = 8362162262476800, which contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 8112 + ... + 13968.

It is an arithmetic number, because the mean of its divisors is an integer number (2214324).

Almost surely, 2^64661280 is an apocalyptic number.

64661280 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 64661280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106287552).

64661280 is an abundant number, since it is smaller than the sum of its proper divisors (147913824).

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

64661280 is a wasteful number, since it uses less digits than its factorization.

64661280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5898 (or 5890 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 64661280 is about 8041.2237874592. The cubic root of 64661280 is about 401.3729488040.

The spelling of 64661280 in words is "sixty-four million, six hundred sixty-one thousand, two hundred eighty".