30724321 has 4 divisors (see below), whose sum is σ = 32531652. Its totient is φ = 28916992.

The previous prime is 30724289. The next prime is 30724333. The reversal of 30724321 is 12342703.

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 17943696 + 12780625 = 4236^2 + 3575^2 .

It is a cyclic number.

It is not a de Polignac number, because 30724321 - 2⁵ = 30724289 is a prime.

It is a super-2 number, since 2×30724321² = 1887967801822082, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 30724292 and 30724301.

It is not an unprimeable number, because it can be changed into a prime (30724721) 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, 903640 + ... + 903673.

It is an arithmetic number, because the mean of its divisors is an integer number (8132913).

Almost surely, 2^30724321 is an apocalyptic number.

It is an amenable number.

30724321 is a deficient number, since it is larger than the sum of its proper divisors (1807331).

30724321 is a wasteful number, since it uses less digits than its factorization.

30724321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1807330.

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 30724321 is about 5542.9523721569. The cubic root of 30724321 is about 313.2040947571.

The spelling of 30724321 in words is "thirty million, seven hundred twenty-four thousand, three hundred twenty-one".