68945821 has 4 divisors (see below), whose sum is σ = 78795232. Its totient is φ = 59096412.

The previous prime is 68945803. The next prime is 68945827. The reversal of 68945821 is 12854986.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12854986 = 2 ⋅6427493.

It is a cyclic number.

It is not a de Polignac number, because 68945821 - 2¹¹ = 68943773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68945827) 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, 4924695 + ... + 4924708.

It is an arithmetic number, because the mean of its divisors is an integer number (19698808).

Almost surely, 2^68945821 is an apocalyptic number.

It is an amenable number.

68945821 is a deficient number, since it is larger than the sum of its proper divisors (9849411).

68945821 is an equidigital number, since it uses as much as digits as its factorization.

68945821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9849410.

The product of its digits is 138240, while the sum is 43.

The square root of 68945821 is about 8303.3620299250. The cubic root of 68945821 is about 410.0492128117.

The spelling of 68945821 in words is "sixty-eight million, nine hundred forty-five thousand, eight hundred twenty-one".