1889645495909 has 2 divisors, whose sum is σ = 1889645495910. Its totient is φ = 1889645495908.

The previous prime is 1889645495891. The next prime is 1889645495963. The reversal of 1889645495909 is 9095945469881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1258132372225 + 631513123684 = 1121665^2 + 794678^2 .

It is a cyclic number.

It is not a de Polignac number, because 1889645495909 - 2¹⁶ = 1889645430373 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1889645495909.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1889645495989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 944822747954 + 944822747955.

It is an arithmetic number, because the mean of its divisors is an integer number (944822747955).

Almost surely, 2^{1889645495909} is an apocalyptic number.

It is an amenable number.

1889645495909 is a deficient number, since it is larger than the sum of its proper divisors (1).

1889645495909 is an equidigital number, since it uses as much as digits as its factorization.

1889645495909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1007769600, while the sum is 77.

The spelling of 1889645495909 in words is "one trillion, eight hundred eighty-nine billion, six hundred forty-five million, four hundred ninety-five thousand, nine hundred nine".