731664 has 30 divisors (see below), whose sum is σ = 2048046. Its totient is φ = 243840.

The previous prime is 731651. The next prime is 731681. The reversal of 731664 is 466137.

It can be written as a sum of positive squares in only one way, i.e., 501264 + 230400 = 708^2 + 480^2 .

It is an unprimeable number.

731664 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2397 + ... + 2684.

2⁷³¹⁶⁶⁴ is an apocalyptic number.

It is an amenable number.

731664 is an abundant number, since it is smaller than the sum of its proper divisors (1316382).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

731664 is a wasteful number, since it uses less digits than its factorization.

731664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5095 (or 5086 counting only the distinct ones).

The product of its digits is 3024, while the sum is 27.

The square root of 731664 is about 855.3736025854. The cubic root of 731664 is about 90.1094963595.

The spelling of 731664 in words is "seven hundred thirty-one thousand, six hundred sixty-four".