30821217 has 16 divisors (see below), whose sum is σ = 48112512. Its totient is φ = 17182080.

The previous prime is 30821207. The next prime is 30821251. The reversal of 30821217 is 71212803.

It is not a de Polignac number, because 30821217 - 2⁸ = 30820961 is a prime.

It is a super-2 number, since 2×30821217² = 1899894834722178, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (30821207) 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 15 ways as a sum of consecutive naturals, for example, 17038 + ... + 18759.

It is an arithmetic number, because the mean of its divisors is an integer number (3007032).

Almost surely, 2^30821217 is an apocalyptic number.

It is an amenable number.

30821217 is a deficient number, since it is larger than the sum of its proper divisors (17291295).

30821217 is a wasteful number, since it uses less digits than its factorization.

30821217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35848.

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 30821217 is about 5551.6859601386. The cubic root of 30821217 is about 313.5330022312.

The spelling of 30821217 in words is "thirty million, eight hundred twenty-one thousand, two hundred seventeen".