68886640 has 20 divisors (see below), whose sum is σ = 160161624. Its totient is φ = 27554624.

The previous prime is 68886617. The next prime is 68886641. The reversal of 68886640 is 4668886.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68886641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 430462 + ... + 430621.

Almost surely, 2^68886640 is an apocalyptic number.

It is an amenable number.

68886640 is an abundant number, since it is smaller than the sum of its proper divisors (91274984).

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

68886640 is a wasteful number, since it uses less digits than its factorization.

68886640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 861096 (or 861090 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 46.

The square root of 68886640 is about 8299.7975878933. The cubic root of 68886640 is about 409.9318546271.

The spelling of 68886640 in words is "sixty-eight million, eight hundred eighty-six thousand, six hundred forty".