19911049 has 2 divisors, whose sum is σ = 19911050. Its totient is φ = 19911048.

The previous prime is 19911041. The next prime is 19911091. The reversal of 19911049 is 94011991.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17640000 + 2271049 = 4200^2 + 1507^2 .

It is a cyclic number.

It is not a de Polignac number, because 19911049 - 2³ = 19911041 is a prime.

It is not a weakly prime, because it can be changed into another prime (19911041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9955524 + 9955525.

It is an arithmetic number, because the mean of its divisors is an integer number (9955525).

Almost surely, 2^19911049 is an apocalyptic number.

It is an amenable number.

19911049 is a deficient number, since it is larger than the sum of its proper divisors (1).

19911049 is an equidigital number, since it uses as much as digits as its factorization.

19911049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2916, while the sum is 34.

The square root of 19911049 is about 4462.1798484597. The cubic root of 19911049 is about 271.0387466555.

The spelling of 19911049 in words is "nineteen million, nine hundred eleven thousand, forty-nine".