681553863 has 12 divisors (see below), whose sum is σ = 991075800. Its totient is φ = 451318896.

The previous prime is 681553861. The next prime is 681553867. The reversal of 681553863 is 368355186.

It is not a de Polignac number, because 681553863 - 2¹ = 681553861 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681553861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 252781 + ... + 255462.

It is an arithmetic number, because the mean of its divisors is an integer number (82589650).

Almost surely, 2^681553863 is an apocalyptic number.

681553863 is a deficient number, since it is larger than the sum of its proper divisors (309521937).

681553863 is a wasteful number, since it uses less digits than its factorization.

681553863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 508398 (or 508395 counting only the distinct ones).

The product of its digits is 518400, while the sum is 45.

The square root of 681553863 is about 26106.5865826998. The cubic root of 681553863 is about 880.0352357620.

The spelling of 681553863 in words is "six hundred eighty-one million, five hundred fifty-three thousand, eight hundred sixty-three".