30356981 has 2 divisors, whose sum is σ = 30356982. Its totient is φ = 30356980.

The previous prime is 30356959. The next prime is 30356999. The reversal of 30356981 is 18965303.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29702500 + 654481 = 5450^2 + 809^2 .

It is a cyclic number.

It is not a de Polignac number, because 30356981 - 2¹⁰ = 30355957 is a prime.

It is a super-2 number, since 2×30356981² = 1843092590868722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30350981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15178490 + 15178491.

It is an arithmetic number, because the mean of its divisors is an integer number (15178491).

Almost surely, 2^30356981 is an apocalyptic number.

It is an amenable number.

30356981 is a deficient number, since it is larger than the sum of its proper divisors (1).

30356981 is an equidigital number, since it uses as much as digits as its factorization.

30356981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19440, while the sum is 35.

The square root of 30356981 is about 5509.7169618774. The cubic root of 30356981 is about 311.9508640844.

The spelling of 30356981 in words is "thirty million, three hundred fifty-six thousand, nine hundred eighty-one".