1891486693 has 2 divisors, whose sum is σ = 1891486694. Its totient is φ = 1891486692.

The previous prime is 1891486687. The next prime is 1891486697. The reversal of 1891486693 is 3966841981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1768875364 + 122611329 = 42058^2 + 11073^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1891486693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1891486697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945743346 + 945743347.

It is an arithmetic number, because the mean of its divisors is an integer number (945743347).

Almost surely, 2^1891486693 is an apocalyptic number.

It is an amenable number.

1891486693 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891486693 is an equidigital number, since it uses as much as digits as its factorization.

1891486693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 55.

The square root of 1891486693 is about 43491.2254713523. The cubic root of 1891486693 is about 1236.7096894222.

The spelling of 1891486693 in words is "one billion, eight hundred ninety-one million, four hundred eighty-six thousand, six hundred ninety-three".