68131291 has 4 divisors (see below), whose sum is σ = 72139032. Its totient is φ = 64123552.

The previous prime is 68131289. The next prime is 68131303. The reversal of 68131291 is 19213186.

68131291 = T₆₇₃₈ + T₆₇₃₉ + T₆₇₄₀.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19213186 = 2 ⋅9606593.

It is a cyclic number.

It is not a de Polignac number, because 68131291 - 2¹ = 68131289 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68131201) 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, 2003845 + ... + 2003878.

It is an arithmetic number, because the mean of its divisors is an integer number (18034758).

Almost surely, 2^68131291 is an apocalyptic number.

68131291 is the 6740-th centered triangular number.

68131291 is a deficient number, since it is larger than the sum of its proper divisors (4007741).

68131291 is a wasteful number, since it uses less digits than its factorization.

68131291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4007740.

The product of its digits is 2592, while the sum is 31.

The square root of 68131291 is about 8254.1680986033. The cubic root of 68131291 is about 408.4280298305.

The spelling of 68131291 in words is "sixty-eight million, one hundred thirty-one thousand, two hundred ninety-one".