68545621 has 4 divisors (see below), whose sum is σ = 69046092. Its totient is φ = 68045152.

The previous prime is 68545579. The next prime is 68545627. The reversal of 68545621 is 12654586.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 59120721 + 9424900 = 7689^2 + 3070^2 .

It is a cyclic number.

It is not a de Polignac number, because 68545621 - 2⁷ = 68545493 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 (68545627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250030 + ... + 250303.

It is an arithmetic number, because the mean of its divisors is an integer number (17261523).

Almost surely, 2^68545621 is an apocalyptic number.

It is an amenable number.

68545621 is a deficient number, since it is larger than the sum of its proper divisors (500471).

68545621 is a wasteful number, since it uses less digits than its factorization.

68545621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500470.

The product of its digits is 57600, while the sum is 37.

The square root of 68545621 is about 8279.2282852933. The cubic root of 68545621 is about 409.2542879801.

The spelling of 68545621 in words is "sixty-eight million, five hundred forty-five thousand, six hundred twenty-one".