30993251 has 2 divisors, whose sum is σ = 30993252. Its totient is φ = 30993250.

The previous prime is 30993139. The next prime is 30993269. The reversal of 30993251 is 15239903.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30993251 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (30993451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15496625 + 15496626.

It is an arithmetic number, because the mean of its divisors is an integer number (15496626).

Almost surely, 2^30993251 is an apocalyptic number.

30993251 is a deficient number, since it is larger than the sum of its proper divisors (1).

30993251 is an equidigital number, since it uses as much as digits as its factorization.

30993251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7290, while the sum is 32.

The square root of 30993251 is about 5567.1582517475. The cubic root of 30993251 is about 314.1152666189.

The spelling of 30993251 in words is "thirty million, nine hundred ninety-three thousand, two hundred fifty-one".