68912809 has 4 divisors (see below), whose sum is σ = 78757504. Its totient is φ = 59068116.

The previous prime is 68912797. The next prime is 68912821. The reversal of 68912809 is 90821986.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (68912797) and next prime (68912821).

It is a cyclic number.

It is not a de Polignac number, because 68912809 - 2¹⁷ = 68781737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (68912839) 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, 4922337 + ... + 4922350.

It is an arithmetic number, because the mean of its divisors is an integer number (19689376).

Almost surely, 2^68912809 is an apocalyptic number.

It is an amenable number.

68912809 is a deficient number, since it is larger than the sum of its proper divisors (9844695).

68912809 is an equidigital number, since it uses as much as digits as its factorization.

68912809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9844694.

The product of its (nonzero) digits is 62208, while the sum is 43.

The square root of 68912809 is about 8301.3739224299. The cubic root of 68912809 is about 409.9837570404.

The spelling of 68912809 in words is "sixty-eight million, nine hundred twelve thousand, eight hundred nine".