68643855 has 72 divisors (see below), whose sum is σ = 143659152. Its totient is φ = 31352832.

The previous prime is 68643833. The next prime is 68643857. The reversal of 68643855 is 55834686.

It is not a de Polignac number, because 68643855 - 2¹⁰ = 68642831 is a prime.

It is a super-2 number, since 2×68643855² = 9423957658522050, which contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 68643855.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68643857) by changing a digit.

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 71 ways as a sum of consecutive naturals, for example, 58959 + ... + 60111.

It is an arithmetic number, because the mean of its divisors is an integer number (1995266).

Almost surely, 2^68643855 is an apocalyptic number.

68643855 is an abundant number, since it is smaller than the sum of its proper divisors (75015297).

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

68643855 is a wasteful number, since it uses less digits than its factorization.

68643855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1187 (or 1168 counting only the distinct ones).

The product of its digits is 691200, while the sum is 45.

The square root of 68643855 is about 8285.1587190590. The cubic root of 68643855 is about 409.4496979633.

The spelling of 68643855 in words is "sixty-eight million, six hundred forty-three thousand, eight hundred fifty-five".