68309280 has 288 divisors, whose sum is σ = 260048880. Its totient is φ = 16220160.

The previous prime is 68309279. The next prime is 68309303. The reversal of 68309280 is 8290386.

It can be written as a sum of positive squares in 8 ways, for example, as 345744 + 67963536 = 588^2 + 8244^2 .

It is a tau number, because it is divible by the number of its divisors (288).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 767476 + ... + 767564.

Almost surely, 2^68309280 is an apocalyptic number.

68309280 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 68309280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130024440).

68309280 is an abundant number, since it is smaller than the sum of its proper divisors (191739600).

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

68309280 is a wasteful number, since it uses less digits than its factorization.

68309280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164 (or 153 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 68309280 is about 8264.9428310183. The cubic root of 68309280 is about 408.7833853157.

It can be divided in two parts, 6830 and 9280, that added together give a triangular number (16110 = T₁₇₉).

The spelling of 68309280 in words is "sixty-eight million, three hundred nine thousand, two hundred eighty".