68371721 has 4 divisors (see below), whose sum is σ = 74587344. Its totient is φ = 62156100.

The previous prime is 68371717. The next prime is 68371741. The reversal of 68371721 is 12717386.

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 68371721 - 2² = 68371717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68371741) 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, 3107795 + ... + 3107816.

It is an arithmetic number, because the mean of its divisors is an integer number (18646836).

Almost surely, 2^68371721 is an apocalyptic number.

It is an amenable number.

68371721 is a deficient number, since it is larger than the sum of its proper divisors (6215623).

68371721 is a wasteful number, since it uses less digits than its factorization.

68371721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6215622.

The product of its digits is 14112, while the sum is 35.

The square root of 68371721 is about 8268.7194292708. The cubic root of 68371721 is about 408.9079026577.

It can be divided in two parts, 6837 and 1721, that added together give a palindrome (8558).

The spelling of 68371721 in words is "sixty-eight million, three hundred seventy-one thousand, seven hundred twenty-one".