1890000649 has 2 divisors, whose sum is σ = 1890000650. Its totient is φ = 1890000648.

The previous prime is 1890000647. The next prime is 1890000683. The reversal of 1890000649 is 9460000981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1020163600 + 869837049 = 31940^2 + 29493^2 .

It is a cyclic number.

It is not a de Polignac number, because 1890000649 - 2¹ = 1890000647 is a prime.

Together with 1890000647, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1890000647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945000324 + 945000325.

It is an arithmetic number, because the mean of its divisors is an integer number (945000325).

Almost surely, 2^1890000649 is an apocalyptic number.

It is an amenable number.

1890000649 is a deficient number, since it is larger than the sum of its proper divisors (1).

1890000649 is an equidigital number, since it uses as much as digits as its factorization.

1890000649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 1890000649 is about 43474.1377027768. The cubic root of 1890000649 is about 1236.3857314618.

The spelling of 1890000649 in words is "one billion, eight hundred ninety million, six hundred forty-nine", and thus it is an aban number.