68186640 has 40 divisors (see below), whose sum is σ = 211379328. Its totient is φ = 18183040.

The previous prime is 68186633. The next prime is 68186641. The reversal of 68186640 is 4668186.

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

It is not an unprimeable number, because it can be changed into a prime (68186641) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 141816 + ... + 142295.

Almost surely, 2^68186640 is an apocalyptic number.

68186640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

68186640 is an abundant number, since it is smaller than the sum of its proper divisors (143192688).

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

68186640 is a wasteful number, since it uses less digits than its factorization.

68186640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284127 (or 284121 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 39.

The square root of 68186640 is about 8257.5202088763. The cubic root of 68186640 is about 408.5386004842.

The spelling of 68186640 in words is "sixty-eight million, one hundred eighty-six thousand, six hundred forty".