681006203361 has 81 divisors (see below), whose sum is σ = 1149354636339. Its totient is φ = 388188662400.

The previous prime is 681006203329. The next prime is 681006203413. The reversal of 681006203361 is 163302600186.

The square root of 681006203361 is 825231.

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

It can be written as a sum of positive squares in only one way, i.e., 530195141025 + 150811062336 = 728145^2 + 388344^2 .

It is not a de Polignac number, because 681006203361 - 2⁵ = 681006203329 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (681006203861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 462953856 + ... + 462955326.

Almost surely, 2^681006203361 is an apocalyptic number.

681006203361 is the 825231-st square number.

681006203361 is the 412616-th centered octagonal number.

It is an amenable number.

681006203361 is a deficient number, since it is larger than the sum of its proper divisors (468348432978).

681006203361 is a wasteful number, since it uses less digits than its factorization.

681006203361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3004 (or 1502 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

Multiplying 681006203361 by its sum of digits (36), we get a square (24516223320996 = 4951386²).

The spelling of 681006203361 in words is "six hundred eighty-one billion, six million, two hundred three thousand, three hundred sixty-one".