731665 has 16 divisors (see below), whose sum is σ = 979776. Its totient is φ = 520000.

The previous prime is 731651. The next prime is 731681. The reversal of 731665 is 566137.

It is not a de Polignac number, because 731665 - 2¹³ = 723473 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2790 + ... + 3040.

It is an arithmetic number, because the mean of its divisors is an integer number (61236).

2⁷³¹⁶⁶⁵ is an apocalyptic number.

It is an amenable number.

731665 is a deficient number, since it is larger than the sum of its proper divisors (248111).

731665 is a wasteful number, since it uses less digits than its factorization.

731665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320.

The product of its digits is 3780, while the sum is 28.

The square root of 731665 is about 855.3741871251. The cubic root of 731665 is about 90.1095374118.

It can be divided in two parts, 7316 and 65, that added together give a triangular number (7381 = T₁₂₁).

The spelling of 731665 in words is "seven hundred thirty-one thousand, six hundred sixty-five".