1216427687 has 4 divisors (see below), whose sum is σ = 1216544016. Its totient is φ = 1216311360.

The previous prime is 1216427659. The next prime is 1216427699. The reversal of 1216427687 is 7867246121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1216427687 - 2⁸ = 1216427431 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216427087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40739 + ... + 63972.

It is an arithmetic number, because the mean of its divisors is an integer number (304136004).

Almost surely, 2^1216427687 is an apocalyptic number.

1216427687 is a deficient number, since it is larger than the sum of its proper divisors (116329).

1216427687 is a wasteful number, since it uses less digits than its factorization.

1216427687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116328.

The product of its digits is 225792, while the sum is 44.

The square root of 1216427687 is about 34877.3233921412. The cubic root of 1216427687 is about 1067.4857808621.

The spelling of 1216427687 in words is "one billion, two hundred sixteen million, four hundred twenty-seven thousand, six hundred eighty-seven".