68191811 has 4 divisors (see below), whose sum is σ = 72203112. Its totient is φ = 64180512.

The previous prime is 68191801. The next prime is 68191813. The reversal of 68191811 is 11819186.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68191811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68191813) 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, 2005625 + ... + 2005658.

It is an arithmetic number, because the mean of its divisors is an integer number (18050778).

Almost surely, 2^68191811 is an apocalyptic number.

68191811 is a deficient number, since it is larger than the sum of its proper divisors (4011301).

68191811 is a wasteful number, since it uses less digits than its factorization.

68191811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4011300.

The product of its digits is 3456, while the sum is 35.

The square root of 68191811 is about 8257.8333114686. The cubic root of 68191811 is about 408.5489275302.

The spelling of 68191811 in words is "sixty-eight million, one hundred ninety-one thousand, eight hundred eleven".