30981287 has 2 divisors, whose sum is σ = 30981288. Its totient is φ = 30981286.

The previous prime is 30981283. The next prime is 30981289. The reversal of 30981287 is 78218903.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 30981287 - 2² = 30981283 is a prime.

Together with 30981289, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30981287.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30981283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15490643 + 15490644.

It is an arithmetic number, because the mean of its divisors is an integer number (15490644).

Almost surely, 2^30981287 is an apocalyptic number.

30981287 is a deficient number, since it is larger than the sum of its proper divisors (1).

30981287 is an equidigital number, since it uses as much as digits as its factorization.

30981287 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 30981287 is about 5566.0836321421. The cubic root of 30981287 is about 314.0748432085.

The spelling of 30981287 in words is "thirty million, nine hundred eighty-one thousand, two hundred eighty-seven".