19138897 has 2 divisors, whose sum is σ = 19138898. Its totient is φ = 19138896.

The previous prime is 19138891. The next prime is 19138919. The reversal of 19138897 is 79883191.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18671041 + 467856 = 4321^2 + 684^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19138897 is a prime.

It is not a weakly prime, because it can be changed into another prime (19138891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9569448 + 9569449.

It is an arithmetic number, because the mean of its divisors is an integer number (9569449).

Almost surely, 2^19138897 is an apocalyptic number.

It is an amenable number.

19138897 is a deficient number, since it is larger than the sum of its proper divisors (1).

19138897 is an equidigital number, since it uses as much as digits as its factorization.

19138897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 46.

The square root of 19138897 is about 4374.8025098283. The cubic root of 19138897 is about 267.4888200993.

The spelling of 19138897 in words is "nineteen million, one hundred thirty-eight thousand, eight hundred ninety-seven".