681326473 has 4 divisors (see below), whose sum is σ = 699740740. Its totient is φ = 662912208.

The previous prime is 681326467. The next prime is 681326483. The reversal of 681326473 is 374623186.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 476636224 + 204690249 = 21832^2 + 14307^2 .

It is a cyclic number.

It is not a de Polignac number, because 681326473 - 2²¹ = 679229321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681326413) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9207078 + ... + 9207151.

It is an arithmetic number, because the mean of its divisors is an integer number (174935185).

Almost surely, 2^681326473 is an apocalyptic number.

It is an amenable number.

681326473 is a deficient number, since it is larger than the sum of its proper divisors (18414267).

681326473 is a wasteful number, since it uses less digits than its factorization.

681326473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18414266.

The product of its digits is 145152, while the sum is 40.

The square root of 681326473 is about 26102.2311881571. The cubic root of 681326473 is about 879.9373547864.

The spelling of 681326473 in words is "six hundred eighty-one million, three hundred twenty-six thousand, four hundred seventy-three".