1891376749 has 2 divisors, whose sum is σ = 1891376750. Its totient is φ = 1891376748.

The previous prime is 1891376731. The next prime is 1891376777. The reversal of 1891376749 is 9476731981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1430201124 + 461175625 = 37818^2 + 21475^2 .

It is a cyclic number.

It is not a de Polignac number, because 1891376749 - 2⁷ = 1891376621 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1891376749.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1891376719) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945688374 + 945688375.

It is an arithmetic number, because the mean of its divisors is an integer number (945688375).

Almost surely, 2^1891376749 is an apocalyptic number.

It is an amenable number.

1891376749 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891376749 is an equidigital number, since it uses as much as digits as its factorization.

1891376749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2286144, while the sum is 55.

The square root of 1891376749 is about 43489.9614738850. The cubic root of 1891376749 is about 1236.6857274165.

The spelling of 1891376749 in words is "one billion, eight hundred ninety-one million, three hundred seventy-six thousand, seven hundred forty-nine".