30974821 has 4 divisors (see below), whose sum is σ = 30991500. Its totient is φ = 30958144.

The previous prime is 30974773. The next prime is 30974851. The reversal of 30974821 is 12847903.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12847903 = 17 ⋅755759.

It can be written as a sum of positive squares in 2 ways, for example, as 17181025 + 13793796 = 4145^2 + 3714^2 .

It is a cyclic number.

It is not a de Polignac number, because 30974821 - 2⁹ = 30974309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30974851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5146 + ... + 9403.

It is an arithmetic number, because the mean of its divisors is an integer number (7747875).

Almost surely, 2^30974821 is an apocalyptic number.

It is an amenable number.

30974821 is a deficient number, since it is larger than the sum of its proper divisors (16679).

30974821 is a wasteful number, since it uses less digits than its factorization.

30974821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16678.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 30974821 is about 5565.5027625543. The cubic root of 30974821 is about 314.0529918543.

The spelling of 30974821 in words is "thirty million, nine hundred seventy-four thousand, eight hundred twenty-one".