68207621 has 4 divisors (see below), whose sum is σ = 72219852. Its totient is φ = 64195392.

The previous prime is 68207617. The next prime is 68207647. The reversal of 68207621 is 12670286.

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 57547396 + 10660225 = 7586^2 + 3265^2 .

It is a cyclic number.

It is not a de Polignac number, because 68207621 - 2² = 68207617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68207221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2006090 + ... + 2006123.

It is an arithmetic number, because the mean of its divisors is an integer number (18054963).

Almost surely, 2^68207621 is an apocalyptic number.

It is an amenable number.

68207621 is a deficient number, since it is larger than the sum of its proper divisors (4012231).

68207621 is a wasteful number, since it uses less digits than its factorization.

68207621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4012230.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 68207621 is about 8258.7905288850. The cubic root of 68207621 is about 408.5804985714.

It can be divided in two parts, 6820 and 7621, that added together give a palindrome (14441).

The spelling of 68207621 in words is "sixty-eight million, two hundred seven thousand, six hundred twenty-one".