1242020191 has 2 divisors, whose sum is σ = 1242020192. Its totient is φ = 1242020190.

The previous prime is 1242020173. The next prime is 1242020203. The reversal of 1242020191 is 1910202421.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1242020191 - 2⁵ = 1242020159 is a prime.

It is a super-2 number, since 2×1242020191² = 3085228309703352962, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1242024191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621010095 + 621010096.

It is an arithmetic number, because the mean of its divisors is an integer number (621010096).

Almost surely, 2^1242020191 is an apocalyptic number.

1242020191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242020191 is an equidigital number, since it uses as much as digits as its factorization.

1242020191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 1242020191 is about 35242.3068342582. The cubic root of 1242020191 is about 1074.9201861782.

The spelling of 1242020191 in words is "one billion, two hundred forty-two million, twenty thousand, one hundred ninety-one".