681244388129 has 16 divisors (see below), whose sum is σ = 722593643904. Its totient is φ = 640874889600.

The previous prime is 681244388107. The next prime is 681244388147. The reversal of 681244388129 is 921883442186.

681244388129 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 681244388129 - 2¹² = 681244384033 is a prime.

It is a super-2 number, since 2×681244388129² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681244388189) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17505437 + ... + 17544309.

It is an arithmetic number, because the mean of its divisors is an integer number (45162102744).

Almost surely, 2^681244388129 is an apocalyptic number.

It is an amenable number.

681244388129 is a deficient number, since it is larger than the sum of its proper divisors (41349255775).

681244388129 is a wasteful number, since it uses less digits than its factorization.

681244388129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51448.

The product of its digits is 5308416, while the sum is 56.

The spelling of 681244388129 in words is "six hundred eighty-one billion, two hundred forty-four million, three hundred eighty-eight thousand, one hundred twenty-nine".