1285941889 has 2 divisors, whose sum is σ = 1285941890. Its totient is φ = 1285941888.

The previous prime is 1285941871. The next prime is 1285941913. The reversal of 1285941889 is 9881495821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 663938289 + 622003600 = 25767^2 + 24940^2 .

It is a cyclic number.

It is not a de Polignac number, because 1285941889 - 2¹³ = 1285933697 is a prime.

It is not a weakly prime, because it can be changed into another prime (1285981889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 642970944 + 642970945.

It is an arithmetic number, because the mean of its divisors is an integer number (642970945).

Almost surely, 2^1285941889 is an apocalyptic number.

It is an amenable number.

1285941889 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285941889 is an equidigital number, since it uses as much as digits as its factorization.

1285941889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1658880, while the sum is 55.

The square root of 1285941889 is about 35860.0319157694. The cubic root of 1285941889 is about 1087.4445336400. Note that the first 3 decimals are identical.

The spelling of 1285941889 in words is "one billion, two hundred eighty-five million, nine hundred forty-one thousand, eight hundred eighty-nine".