1219128687 has 24 divisors (see below), whose sum is σ = 2013464960. Its totient is φ = 696321360.

The previous prime is 1219128649. The next prime is 1219128719. The reversal of 1219128687 is 7868219121.

It is not a de Polignac number, because 1219128687 - 2⁸ = 1219128431 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1219128607) 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 in 23 ways as a sum of consecutive naturals, for example, 222264 + ... + 227682.

Almost surely, 2^1219128687 is an apocalyptic number.

1219128687 is a deficient number, since it is larger than the sum of its proper divisors (794336273).

1219128687 is a wasteful number, since it uses less digits than its factorization.

1219128687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9003 (or 9000 counting only the distinct ones).

The product of its digits is 96768, while the sum is 45.

The square root of 1219128687 is about 34916.0233560467. The cubic root of 1219128687 is about 1068.2752914670.

The spelling of 1219128687 in words is "one billion, two hundred nineteen million, one hundred twenty-eight thousand, six hundred eighty-seven".