68309136 has 160 divisors (see below), whose sum is σ = 229152000. Its totient is φ = 19474560.

The previous prime is 68309071. The next prime is 68309173. The reversal of 68309136 is 63190386.

It is a happy number.

It is a super-2 number, since 2×68309136² = 9332276122132992, which contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 68309136.

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 31 ways as a sum of consecutive naturals, for example, 147946 + ... + 148406.

It is an arithmetic number, because the mean of its divisors is an integer number (1432200).

Almost surely, 2^68309136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 68309136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114576000).

68309136 is an abundant number, since it is smaller than the sum of its proper divisors (160842864).

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

68309136 is a wasteful number, since it uses less digits than its factorization.

68309136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499 (or 473 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 68309136 is about 8264.9341195196. The cubic root of 68309136 is about 408.7830980689.

The spelling of 68309136 in words is "sixty-eight million, three hundred nine thousand, one hundred thirty-six".