30981217 has 4 divisors (see below), whose sum is σ = 31006720. Its totient is φ = 30955716.

The previous prime is 30981163. The next prime is 30981239. The reversal of 30981217 is 71218903.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30981217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30981257) 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, 10833 + ... + 13390.

It is an arithmetic number, because the mean of its divisors is an integer number (7751680).

Almost surely, 2^30981217 is an apocalyptic number.

It is an amenable number.

30981217 is a deficient number, since it is larger than the sum of its proper divisors (25503).

30981217 is a wasteful number, since it uses less digits than its factorization.

30981217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25502.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 30981217 is about 5566.0773440548. The cubic root of 30981217 is about 314.0746066651.

The spelling of 30981217 in words is "thirty million, nine hundred eighty-one thousand, two hundred seventeen".