1889191361 has 2 divisors, whose sum is σ = 1889191362. Its totient is φ = 1889191360.

The previous prime is 1889191349. The next prime is 1889191363. The reversal of 1889191361 is 1631919881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1688799025 + 200392336 = 41095^2 + 14156^2 .

It is a cyclic number.

It is not a de Polignac number, because 1889191361 - 2²² = 1884997057 is a prime.

Together with 1889191363, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1889191363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 944595680 + 944595681.

It is an arithmetic number, because the mean of its divisors is an integer number (944595681).

Almost surely, 2^1889191361 is an apocalyptic number.

It is an amenable number.

1889191361 is a deficient number, since it is larger than the sum of its proper divisors (1).

1889191361 is an equidigital number, since it uses as much as digits as its factorization.

1889191361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 47.

The square root of 1889191361 is about 43464.8290115123. The cubic root of 1889191361 is about 1236.2092350523.

The spelling of 1889191361 in words is "one billion, eight hundred eighty-nine million, one hundred ninety-one thousand, three hundred sixty-one".