987946391 has 2 divisors, whose sum is σ = 987946392. Its totient is φ = 987946390.

The previous prime is 987946367. The next prime is 987946411. The reversal of 987946391 is 193649789.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 987946391 - 2¹⁰ = 987945367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (987946321) 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, 493973195 + 493973196.

It is an arithmetic number, because the mean of its divisors is an integer number (493973196).

Almost surely, 2^987946391 is an apocalyptic number.

987946391 is a deficient number, since it is larger than the sum of its proper divisors (1).

987946391 is an equidigital number, since it uses as much as digits as its factorization.

987946391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2939328, while the sum is 56.

The square root of 987946391 is about 31431.6145146889. The cubic root of 987946391 is about 995.9658780776.

The spelling of 987946391 in words is "nine hundred eighty-seven million, nine hundred forty-six thousand, three hundred ninety-one".