• 730 can be written using four 4's:

See also 113.

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730 has 8 divisors (see below), whose sum is σ = 1332. Its totient is φ = 288.

The previous prime is 727. The next prime is 733. The reversal of 730 is 37.

730 = 10² + 11² + ... + 14².

730 is nontrivially palindromic in base 3 and base 9.

It is a Cunningham number, because it is equal to 3⁶+1.

It is an interprime number because it is at equal distance from previous prime (727) and next prime (733).

It can be written as a sum of positive squares in 2 ways, for example, as 729 + 1 = 27^2 + 1^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (10), and also a Moran number because the ratio is a prime number: 73 = 730 / (7 + 3 + 0).

It is a magnanimous number.

It is a plaindrome in base 15.

It is a nialpdrome in base 10 and base 13.

It is not an unprimeable number, because it can be changed into a prime (733) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27 + ... + 46.

730 is a deficient number, since it is larger than the sum of its proper divisors (602).

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

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

The sum of its prime factors is 80.

The product of its (nonzero) digits is 21, while the sum is 10.

The square root of 730 is about 27.0185121722. The cubic root of 730 is about 9.0041133461.

Adding to 730 its reverse (37), we get a palindrome (767).

It can be divided in two parts, 7 and 30, that multiplied together give a triangular number (210 = T₂₀).

The spelling of 730 in words is "seven hundred thirty", and thus it is an aban number and an oban number.