19919051 has 2 divisors, whose sum is σ = 19919052. Its totient is φ = 19919050.

The previous prime is 19919041. The next prime is 19919057. The reversal of 19919051 is 15091991.

It is a strong prime.

It is an emirp because it is prime and its reverse (15091991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19919051 is a prime.

It is not a weakly prime, because it can be changed into another prime (19919057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9959525 + 9959526.

It is an arithmetic number, because the mean of its divisors is an integer number (9959526).

Almost surely, 2^19919051 is an apocalyptic number.

19919051 is a deficient number, since it is larger than the sum of its proper divisors (1).

19919051 is an equidigital number, since it uses as much as digits as its factorization.

19919051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3645, while the sum is 35.

The square root of 19919051 is about 4463.0764053509. The cubic root of 19919051 is about 271.0750508129.

The spelling of 19919051 in words is "nineteen million, nine hundred nineteen thousand, fifty-one".