1216759987 has 2 divisors, whose sum is σ = 1216759988. Its totient is φ = 1216759986.

The previous prime is 1216759969. The next prime is 1216760033. The reversal of 1216759987 is 7899576121.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (7899576121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1216759987 - 2¹¹ = 1216757939 is a prime.

It is not a weakly prime, because it can be changed into another prime (1216759927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608379993 + 608379994.

It is an arithmetic number, because the mean of its divisors is an integer number (608379994).

Almost surely, 2^1216759987 is an apocalyptic number.

1216759987 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216759987 is an equidigital number, since it uses as much as digits as its factorization.

1216759987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1905120, while the sum is 55.

The square root of 1216759987 is about 34882.0869071792. The cubic root of 1216759987 is about 1067.5829761804.

The spelling of 1216759987 in words is "one billion, two hundred sixteen million, seven hundred fifty-nine thousand, nine hundred eighty-seven".