30749 has 4 divisors (see below), whose sum is σ = 31164. Its totient is φ = 30336.

The previous prime is 30727. The next prime is 30757. The reversal of 30749 is 94703.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6724 + 24025 = 82^2 + 155^2 .

It is a cyclic number.

It is not a de Polignac number, because 30749 - 2⁸ = 30493 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 30749.

It is not an unprimeable number, because it can be changed into a prime (30449) 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, 62 + ... + 255.

It is an arithmetic number, because the mean of its divisors is an integer number (7791).

2³⁰⁷⁴⁹ is an apocalyptic number.

It is an amenable number.

30749 is a deficient number, since it is larger than the sum of its proper divisors (415).

30749 is an equidigital number, since it uses as much as digits as its factorization.

30749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414.

The product of its (nonzero) digits is 756, while the sum is 23.

The square root of 30749 is about 175.3539278146. The cubic root of 30749 is about 31.3287931654.

The spelling of 30749 in words is "thirty thousand, seven hundred forty-nine".