1891696057 has 2 divisors, whose sum is σ = 1891696058. Its totient is φ = 1891696056.

The previous prime is 1891696021. The next prime is 1891696133. The reversal of 1891696057 is 7506961981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1637739961 + 253956096 = 40469^2 + 15936^2 .

It is an emirp because it is prime and its reverse (7506961981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1891696057 - 2¹¹ = 1891694009 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1891695995 and 1891696013.

It is not a weakly prime, because it can be changed into another prime (1891696357) 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, 945848028 + 945848029.

It is an arithmetic number, because the mean of its divisors is an integer number (945848029).

Almost surely, 2^1891696057 is an apocalyptic number.

It is an amenable number.

1891696057 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891696057 is an equidigital number, since it uses as much as digits as its factorization.

1891696057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 816480, while the sum is 52.

The square root of 1891696057 is about 43493.6323730267. The cubic root of 1891696057 is about 1236.7553171879.

The spelling of 1891696057 in words is "one billion, eight hundred ninety-one million, six hundred ninety-six thousand, fifty-seven".