68640188 has 24 divisors (see below), whose sum is σ = 125798400. Its totient is φ = 32708720.

The previous prime is 68640157. The next prime is 68640193. The reversal of 68640188 is 88104686.

It is a super-2 number, since 2×68640188² = 9422950817350688, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27413 + ... + 29811.

It is an arithmetic number, because the mean of its divisors is an integer number (5241600).

Almost surely, 2^68640188 is an apocalyptic number.

It is an amenable number.

68640188 is a deficient number, since it is larger than the sum of its proper divisors (57158212).

68640188 is a wasteful number, since it uses less digits than its factorization.

68640188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2737 (or 2735 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 41.

The square root of 68640188 is about 8284.9374167823. The cubic root of 68640188 is about 409.4424068092.

The spelling of 68640188 in words is "sixty-eight million, six hundred forty thousand, one hundred eighty-eight".