68858721 has 32 divisors (see below), whose sum is σ = 110678400. Its totient is φ = 42140160.

The previous prime is 68858707. The next prime is 68858729. The reversal of 68858721 is 12785886.

68858721 is a `hidden beast` number, since 68 + 8 + 587 + 2 + 1 = 666.

It is not a de Polignac number, because 68858721 - 2⁵ = 68858689 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (68858729) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16990 + ... + 20648.

It is an arithmetic number, because the mean of its divisors is an integer number (3458700).

Almost surely, 2^68858721 is an apocalyptic number.

It is an amenable number.

68858721 is a deficient number, since it is larger than the sum of its proper divisors (41819679).

68858721 is a wasteful number, since it uses less digits than its factorization.

68858721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3726 (or 3720 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 68858721 is about 8298.1155089574. The cubic root of 68858721 is about 409.8764668482.

The spelling of 68858721 in words is "sixty-eight million, eight hundred fifty-eight thousand, seven hundred twenty-one".