68644689 has 4 divisors (see below), whose sum is σ = 91526256. Its totient is φ = 45763124.

The previous prime is 68644661. The next prime is 68644787. The reversal of 68644689 is 98644686.

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 a cyclic number.

It is not a de Polignac number, because 68644689 - 2²³ = 60256081 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (68642689) 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, 11440779 + ... + 11440784.

It is an arithmetic number, because the mean of its divisors is an integer number (22881564).

Almost surely, 2^68644689 is an apocalyptic number.

It is an amenable number.

68644689 is a deficient number, since it is larger than the sum of its proper divisors (22881567).

68644689 is a wasteful number, since it uses less digits than its factorization.

68644689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22881566.

The product of its digits is 1990656, while the sum is 51.

The square root of 68644689 is about 8285.2090498671. The cubic root of 68644689 is about 409.4513561824.

The spelling of 68644689 in words is "sixty-eight million, six hundred forty-four thousand, six hundred eighty-nine".