30443981 has 2 divisors, whose sum is σ = 30443982. Its totient is φ = 30443980.

The previous prime is 30443977. The next prime is 30443983. The reversal of 30443981 is 18934403.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21473956 + 8970025 = 4634^2 + 2995^2 .

It is a cyclic number.

It is not a de Polignac number, because 30443981 - 2² = 30443977 is a prime.

It is a super-2 number, since 2×30443981² = 1853671958256722, which contains 22 as substring.

Together with 30443983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30443983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15221990 + 15221991.

It is an arithmetic number, because the mean of its divisors is an integer number (15221991).

Almost surely, 2^30443981 is an apocalyptic number.

It is an amenable number.

30443981 is a deficient number, since it is larger than the sum of its proper divisors (1).

30443981 is an equidigital number, since it uses as much as digits as its factorization.

30443981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 30443981 is about 5517.6064557016. The cubic root of 30443981 is about 312.2485862659.

The spelling of 30443981 in words is "thirty million, four hundred forty-three thousand, nine hundred eighty-one".