1209158987 has 2 divisors, whose sum is σ = 1209158988. Its totient is φ = 1209158986.

The previous prime is 1209158953. The next prime is 1209159037. The reversal of 1209158987 is 7898519021.

It is an a-pointer prime, because the next prime (1209159037) can be obtained adding 1209158987 to its sum of digits (50).

It is a weak prime.

It is an emirp because it is prime and its reverse (7898519021) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1209158987 - 2²⁰ = 1208110411 is a prime.

It is not a weakly prime, because it can be changed into another prime (1209158387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 604579493 + 604579494.

It is an arithmetic number, because the mean of its divisors is an integer number (604579494).

Almost surely, 2^1209158987 is an apocalyptic number.

1209158987 is a deficient number, since it is larger than the sum of its proper divisors (1).

1209158987 is an equidigital number, since it uses as much as digits as its factorization.

1209158987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 50.

The square root of 1209158987 is about 34772.9634486335. The cubic root of 1209158987 is about 1065.3552965336.

The spelling of 1209158987 in words is "one billion, two hundred nine million, one hundred fifty-eight thousand, nine hundred eighty-seven".