1631116787 has 2 divisors, whose sum is σ = 1631116788. Its totient is φ = 1631116786.

The previous prime is 1631116777. The next prime is 1631116813. The reversal of 1631116787 is 7876111361.

It is a weak prime.

It is an emirp because it is prime and its reverse (7876111361) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1631116787 is a prime.

It is not a weakly prime, because it can be changed into another prime (1631116727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 815558393 + 815558394.

It is an arithmetic number, because the mean of its divisors is an integer number (815558394).

Almost surely, 2^1631116787 is an apocalyptic number.

1631116787 is a deficient number, since it is larger than the sum of its proper divisors (1).

1631116787 is an equidigital number, since it uses as much as digits as its factorization.

1631116787 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 41.

The square root of 1631116787 is about 40387.0868843000. The cubic root of 1631116787 is about 1177.1406366667.

The spelling of 1631116787 in words is "one billion, six hundred thirty-one million, one hundred sixteen thousand, seven hundred eighty-seven".