1897139 has 2 divisors, whose sum is σ = 1897140. Its totient is φ = 1897138.

The previous prime is 1897127. The next prime is 1897141. The reversal of 1897139 is 9317981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1897139 - 2⁸ = 1896883 is a prime.

It is a Sophie Germain prime.

Together with 1897141, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1897199) 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, 948569 + 948570.

It is an arithmetic number, because the mean of its divisors is an integer number (948570).

2^1897139 is an apocalyptic number.

1897139 is a deficient number, since it is larger than the sum of its proper divisors (1).

1897139 is an equidigital number, since it uses as much as digits as its factorization.

1897139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13608, while the sum is 38.

The square root of 1897139 is about 1377.3666904641. The cubic root of 1897139 is about 123.7940345961.

The spelling of 1897139 in words is "one million, eight hundred ninety-seven thousand, one hundred thirty-nine".