68279991 has 8 divisors (see below), whose sum is σ = 98043120. Its totient is φ = 42018432.

The previous prime is 68279989. The next prime is 68280019. The reversal of 68279991 is 19997286.

It is a happy number.

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

It is not a de Polignac number, because 68279991 - 2¹ = 68279989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68279921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 875346 + ... + 875423.

It is an arithmetic number, because the mean of its divisors is an integer number (12255390).

Almost surely, 2^68279991 is an apocalyptic number.

68279991 is a deficient number, since it is larger than the sum of its proper divisors (29763129).

68279991 is a wasteful number, since it uses less digits than its factorization.

68279991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1750785.

The product of its digits is 489888, while the sum is 51.

The square root of 68279991 is about 8263.1707594603. The cubic root of 68279991 is about 408.7249522195.

The spelling of 68279991 in words is "sixty-eight million, two hundred seventy-nine thousand, nine hundred ninety-one".