68740681 has 3 divisors (see below), whose sum is σ = 68748973. Its totient is φ = 68732390.

The previous prime is 68740627. The next prime is 68740687. The reversal of 68740681 is 18604786.

The square root of 68740681 is 8291.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18604786 = 2 ⋅9302393.

It is not a de Polignac number, because 68740681 - 2¹⁷ = 68609609 is a prime.

It is a super-2 number, since 2×68740681² = 9450562448687522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68740687) 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 2 ways as a sum of consecutive naturals, for example, 4146 + ... + 12436.

Almost surely, 2^68740681 is an apocalyptic number.

68740681 is the 8291-st square number.

68740681 is the 4146-th centered octagonal number.

It is an amenable number.

68740681 is a deficient number, since it is larger than the sum of its proper divisors (8292).

68740681 is an frugal number, since it uses more digits than its factorization.

68740681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16582 (or 8291 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The cubic root of 68740681 is about 409.6421247550.

The spelling of 68740681 in words is "sixty-eight million, seven hundred forty thousand, six hundred eighty-one".