30981031 has 2 divisors, whose sum is σ = 30981032. Its totient is φ = 30981030.

The previous prime is 30981029. The next prime is 30981047. The reversal of 30981031 is 13018903.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 30981031 - 2¹ = 30981029 is a prime.

It is a super-2 number, since 2×30981031² = 1919648563645922, which contains 22 as substring.

Together with 30981029, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 30980987 and 30981005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30961031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15490515 + 15490516.

It is an arithmetic number, because the mean of its divisors is an integer number (15490516).

Almost surely, 2^30981031 is an apocalyptic number.

30981031 is a deficient number, since it is larger than the sum of its proper divisors (1).

30981031 is an equidigital number, since it uses as much as digits as its factorization.

30981031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 30981031 is about 5566.0606356740. The cubic root of 30981031 is about 314.0739781338.

Adding to 30981031 its reverse (13018903), we get a palindrome (43999934).

The spelling of 30981031 in words is "thirty million, nine hundred eighty-one thousand, thirty-one".