68640685 has 8 divisors (see below), whose sum is σ = 84284640. Its totient is φ = 53635344.

The previous prime is 68640653. The next prime is 68640701. The reversal of 68640685 is 58604686.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 68640685 - 2⁵ = 68640653 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

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, 159415 + ... + 159844.

It is an arithmetic number, because the mean of its divisors is an integer number (10535580).

Almost surely, 2^68640685 is an apocalyptic number.

It is an amenable number.

68640685 is a deficient number, since it is larger than the sum of its proper divisors (15643955).

68640685 is a wasteful number, since it uses less digits than its factorization.

68640685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319307.

The product of its (nonzero) digits is 276480, while the sum is 43.

The square root of 68640685 is about 8284.9674109196. The cubic root of 68640685 is about 409.4433950173.

The spelling of 68640685 in words is "sixty-eight million, six hundred forty thousand, six hundred eighty-five".