68217040 has 40 divisors (see below), whose sum is σ = 160791048. Its totient is φ = 26910720.

The previous prime is 68217029. The next prime is 68217043. The reversal of 68217040 is 4071286.

68217040 is a nontrivial binomial coefficient, being equal to C(11681, 2).

It can be written as a sum of positive squares in 4 ways, for example, as 8433216 + 59783824 = 2904^2 + 7732^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68217043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1 + ... + 11680.

Almost surely, 2^68217040 is an apocalyptic number.

68217040 is the 11680-th triangular number.

68217040 is the 3894-th centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 68217040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80395524).

68217040 is an abundant number, since it is smaller than the sum of its proper divisors (92574008).

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

68217040 is a wasteful number, since it uses less digits than its factorization.

68217040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11767 (or 11761 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 68217040 is about 8259.3607500823. The cubic root of 68217040 is about 408.5993050847.

It can be divided in two parts, 6821 and 7040, that added together give a triangular number (13861 = T₁₆₆).

The spelling of 68217040 in words is "sixty-eight million, two hundred seventeen thousand, forty".