731681345 has 8 divisors (see below), whose sum is σ = 881283240. Its totient is φ = 583168000.

The previous prime is 731681323. The next prime is 731681347. The reversal of 731681345 is 543186137.

It can be written as a sum of positive squares in 4 ways, for example, as 1168561 + 730512784 = 1081^2 + 27028^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 731681345 - 2¹⁴ = 731664961 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 731681299 and 731681308.

It is not an unprimeable number, because it can be changed into a prime (731681347) 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 7 ways as a sum of consecutive naturals, for example, 270656 + ... + 273345.

It is an arithmetic number, because the mean of its divisors is an integer number (110160405).

Almost surely, 2^731681345 is an apocalyptic number.

It is an amenable number.

731681345 is a deficient number, since it is larger than the sum of its proper divisors (149601895).

731681345 is a wasteful number, since it uses less digits than its factorization.

731681345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544275.

The product of its digits is 60480, while the sum is 38.

The square root of 731681345 is about 27049.6089620534. The cubic root of 731681345 is about 901.1020840619.

The spelling of 731681345 in words is "seven hundred thirty-one million, six hundred eighty-one thousand, three hundred forty-five".