68554813981 has 4 divisors (see below), whose sum is σ = 68778119872. Its totient is φ = 68331508092.

The previous prime is 68554813967. The next prime is 68554814011. The reversal of 68554813981 is 18931845586.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 18931845586 = 2 ⋅9465922793.

It is a cyclic number.

It is not a de Polignac number, because 68554813981 - 2¹¹ = 68554811933 is a prime.

It is a super-2 number, since 2×68554813981² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68554813181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111652485 + ... + 111653098.

It is an arithmetic number, because the mean of its divisors is an integer number (17194529968).

Almost surely, 2^68554813981 is an apocalyptic number.

It is an amenable number.

68554813981 is a deficient number, since it is larger than the sum of its proper divisors (223305891).

68554813981 is a wasteful number, since it uses less digits than its factorization.

68554813981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223305890.

The product of its digits is 8294400, while the sum is 58.

The spelling of 68554813981 in words is "sixty-eight billion, five hundred fifty-four million, eight hundred thirteen thousand, nine hundred eighty-one".