681329573 has 4 divisors (see below), whose sum is σ = 681385440. Its totient is φ = 681273708.

The previous prime is 681329527. The next prime is 681329599. The reversal of 681329573 is 375923186.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 681329573 - 2²⁶ = 614220709 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681529573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 953 + ... + 36926.

It is an arithmetic number, because the mean of its divisors is an integer number (170346360).

Almost surely, 2^681329573 is an apocalyptic number.

It is an amenable number.

681329573 is a deficient number, since it is larger than the sum of its proper divisors (55867).

681329573 is a wasteful number, since it uses less digits than its factorization.

681329573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55866.

The product of its digits is 272160, while the sum is 44.

The square root of 681329573 is about 26102.2905699864. The cubic root of 681329573 is about 879.9386893408.

The spelling of 681329573 in words is "six hundred eighty-one million, three hundred twenty-nine thousand, five hundred seventy-three".