19499897 has 2 divisors, whose sum is σ = 19499898. Its totient is φ = 19499896.

The previous prime is 19499891. The next prime is 19499903. The reversal of 19499897 is 79899491.

It is a balanced prime because it is at equal distance from previous prime (19499891) and next prime (19499903).

It can be written as a sum of positive squares in only one way, i.e., 13169641 + 6330256 = 3629^2 + 2516^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19499897 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19499891) 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, 9749948 + 9749949.

It is an arithmetic number, because the mean of its divisors is an integer number (9749949).

Almost surely, 2^19499897 is an apocalyptic number.

It is an amenable number.

19499897 is a deficient number, since it is larger than the sum of its proper divisors (1).

19499897 is an equidigital number, since it uses as much as digits as its factorization.

19499897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1469664, while the sum is 56.

The square root of 19499897 is about 4415.8687706951. The cubic root of 19499897 is about 269.1601566968.

The spelling of 19499897 in words is "nineteen million, four hundred ninety-nine thousand, eight hundred ninety-seven".