68616221 has 4 divisors (see below), whose sum is σ = 68748444. Its totient is φ = 68484000.

The previous prime is 68616217. The next prime is 68616257. The reversal of 68616221 is 12261686.

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 24393721 + 44222500 = 4939^2 + 6650^2 .

It is a cyclic number.

It is not a de Polignac number, because 68616221 - 2² = 68616217 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 (68616281) 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, 65330 + ... + 66371.

It is an arithmetic number, because the mean of its divisors is an integer number (17187111).

Almost surely, 2^68616221 is an apocalyptic number.

It is an amenable number.

68616221 is a deficient number, since it is larger than the sum of its proper divisors (132223).

68616221 is a wasteful number, since it uses less digits than its factorization.

68616221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132222.

The product of its digits is 6912, while the sum is 32.

The square root of 68616221 is about 8283.4908704000. The cubic root of 68616221 is about 409.3947464476.

The spelling of 68616221 in words is "sixty-eight million, six hundred sixteen thousand, two hundred twenty-one".