68739840 has 432 divisors, whose sum is σ = 281238048. Its totient is φ = 15925248.

The previous prime is 68739817. The next prime is 68739859. The reversal of 68739840 is 4893786.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (432).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4043512 + ... + 4043528.

It is an arithmetic number, because the mean of its divisors is an integer number (651014).

Almost surely, 2^68739840 is an apocalyptic number.

68739840 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 68739840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140619024).

68739840 is an abundant number, since it is smaller than the sum of its proper divisors (212498208).

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

68739840 is a wasteful number, since it uses less digits than its factorization.

68739840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The square root of 68739840 is about 8290.9492821992. The cubic root of 68739840 is about 409.6404541750.

The spelling of 68739840 in words is "sixty-eight million, seven hundred thirty-nine thousand, eight hundred forty".