68401681 has 4 divisors (see below), whose sum is σ = 68599152. Its totient is φ = 68204212.

The previous prime is 68401667. The next prime is 68401687. The reversal of 68401681 is 18610486.

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 68401681 - 2²³ = 60013073 is a prime.

It is a super-2 number, since 2×68401681² = 9357579927251522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68401687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98215 + ... + 98908.

It is an arithmetic number, because the mean of its divisors is an integer number (17149788).

Almost surely, 2^68401681 is an apocalyptic number.

It is an amenable number.

68401681 is a deficient number, since it is larger than the sum of its proper divisors (197471).

68401681 is a wasteful number, since it uses less digits than its factorization.

68401681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197470.

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 68401681 is about 8270.5308777611. The cubic root of 68401681 is about 408.9676207771.

The spelling of 68401681 in words is "sixty-eight million, four hundred one thousand, six hundred eighty-one".