1987858811 has 2 divisors, whose sum is σ = 1987858812. Its totient is φ = 1987858810.

The previous prime is 1987858799. The next prime is 1987858879. The reversal of 1987858811 is 1188587891.

It is a weak prime.

It is an emirp because it is prime and its reverse (1188587891) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1987858811 is a prime.

It is not a weakly prime, because it can be changed into another prime (1987858211) 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, 993929405 + 993929406.

It is an arithmetic number, because the mean of its divisors is an integer number (993929406).

Almost surely, 2^1987858811 is an apocalyptic number.

1987858811 is a deficient number, since it is larger than the sum of its proper divisors (1).

1987858811 is an equidigital number, since it uses as much as digits as its factorization.

1987858811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1290240, while the sum is 56.

The square root of 1987858811 is about 44585.4102930544. The cubic root of 1987858811 is about 1257.3663835201.

The spelling of 1987858811 in words is "one billion, nine hundred eighty-seven million, eight hundred fifty-eight thousand, eight hundred eleven".