987831881 has 2 divisors, whose sum is σ = 987831882. Its totient is φ = 987831880.

The previous prime is 987831857. The next prime is 987831893. The reversal of 987831881 is 188138789.

It is a happy number.

987831881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 724094281 + 263737600 = 26909^2 + 16240^2 .

It is an emirp because it is prime and its reverse (188138789) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 987831881 - 2²⁶ = 920723017 is a prime.

It is a super-2 number, since 2×987831881² = 1951623650239996322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (987831281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493915940 + 493915941.

It is an arithmetic number, because the mean of its divisors is an integer number (493915941).

Almost surely, 2^987831881 is an apocalyptic number.

It is an amenable number.

987831881 is a deficient number, since it is larger than the sum of its proper divisors (1).

987831881 is an equidigital number, since it uses as much as digits as its factorization.

987831881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 774144, while the sum is 53.

The square root of 987831881 is about 31429.7928882772. The cubic root of 987831881 is about 995.9273967523.

The spelling of 987831881 in words is "nine hundred eighty-seven million, eight hundred thirty-one thousand, eight hundred eighty-one".