30138791 has 2 divisors, whose sum is σ = 30138792. Its totient is φ = 30138790.

The previous prime is 30138709. The next prime is 30138799. The reversal of 30138791 is 19783103.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30138791 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30138799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15069395 + 15069396.

It is an arithmetic number, because the mean of its divisors is an integer number (15069396).

Almost surely, 2^30138791 is an apocalyptic number.

30138791 is a deficient number, since it is larger than the sum of its proper divisors (1).

30138791 is an equidigital number, since it uses as much as digits as its factorization.

30138791 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 30138791 is about 5489.8807819478. The cubic root of 30138791 is about 311.2016867748.

The spelling of 30138791 in words is "thirty million, one hundred thirty-eight thousand, seven hundred ninety-one".