681291855 has 24 divisors (see below), whose sum is σ = 1232251488. Its totient is φ = 347557056.

The previous prime is 681291833. The next prime is 681291857. The reversal of 681291855 is 558192186.

It is a happy number.

681291855 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 681291855 - 2⁸ = 681291599 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 681291855.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681291857) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 328092 + ... + 330161.

It is an arithmetic number, because the mean of its divisors is an integer number (51343812).

Almost surely, 2^681291855 is an apocalyptic number.

681291855 is a deficient number, since it is larger than the sum of its proper divisors (550959633).

681291855 is a wasteful number, since it uses less digits than its factorization.

681291855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 658287 (or 658284 counting only the distinct ones).

The product of its digits is 172800, while the sum is 45.

The square root of 681291855 is about 26101.5680563448. The cubic root of 681291855 is about 879.9224514136.

The spelling of 681291855 in words is "six hundred eighty-one million, two hundred ninety-one thousand, eight hundred fifty-five".