731648 has 20 divisors (see below), whose sum is σ = 1462890. Its totient is φ = 365568.

The previous prime is 731639. The next prime is 731651. The reversal of 731648 is 846137.

It can be written as a sum of positive squares in only one way, i.e., 719104 + 12544 = 848^2 + 112^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 731648.

It is an unprimeable number.

731648 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203 + ... + 1226.

2⁷³¹⁶⁴⁸ is an apocalyptic number.

It is an amenable number.

731648 is a deficient number, since it is larger than the sum of its proper divisors (731242).

731648 is an equidigital number, since it uses as much as digits as its factorization.

731648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1447 (or 1431 counting only the distinct ones).

The product of its digits is 4032, while the sum is 29.

The square root of 731648 is about 855.3642498959. The cubic root of 731648 is about 90.1088395177.

The spelling of 731648 in words is "seven hundred thirty-one thousand, six hundred forty-eight".