787891987 has 2 divisors, whose sum is σ = 787891988. Its totient is φ = 787891986.

The previous prime is 787891961. The next prime is 787892009. The reversal of 787891987 is 789198787.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 787891987 - 2²³ = 779503379 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (787891387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 393945993 + 393945994.

It is an arithmetic number, because the mean of its divisors is an integer number (393945994).

Almost surely, 2^787891987 is an apocalyptic number.

787891987 is a deficient number, since it is larger than the sum of its proper divisors (1).

787891987 is an equidigital number, since it uses as much as digits as its factorization.

787891987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14224896, while the sum is 64.

The square root of 787891987 is about 28069.4137274009. The cubic root of 787891987 is about 923.6105702471.

The spelling of 787891987 in words is "seven hundred eighty-seven million, eight hundred ninety-one thousand, nine hundred eighty-seven".