30912381 has 8 divisors (see below), whose sum is σ = 45796160. Its totient is φ = 20608236.

The previous prime is 30912359. The next prime is 30912383. The reversal of 30912381 is 18321903.

It is not a de Polignac number, because 30912381 - 2⁹ = 30911869 is a prime.

It is a super-2 number, since 2×30912381² = 1911150598178322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1144903 = 30912381 / (3 + 0 + 9 + 1 + 2 + 3 + 8 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30912383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 572425 + ... + 572478.

It is an arithmetic number, because the mean of its divisors is an integer number (5724520).

Almost surely, 2^30912381 is an apocalyptic number.

It is an amenable number.

30912381 is a deficient number, since it is larger than the sum of its proper divisors (14883779).

30912381 is a wasteful number, since it uses less digits than its factorization.

30912381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1144912 (or 1144906 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 30912381 is about 5559.8903766172. The cubic root of 30912381 is about 313.8418239937.

The spelling of 30912381 in words is "thirty million, nine hundred twelve thousand, three hundred eighty-one".