1216403587 has 12 divisors (see below), whose sum is σ = 1426149120. Its totient is φ = 1034416656.

The previous prime is 1216403581. The next prime is 1216403593. The reversal of 1216403587 is 7853046121.

It is an interprime number because it is at equal distance from previous prime (1216403581) and next prime (1216403593).

It is not a de Polignac number, because 1216403587 - 2⁷ = 1216403459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216403581) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 91512 + ... + 103957.

It is an arithmetic number, because the mean of its divisors is an integer number (118845760).

Almost surely, 2^1216403587 is an apocalyptic number.

1216403587 is a deficient number, since it is larger than the sum of its proper divisors (209745533).

1216403587 is a wasteful number, since it uses less digits than its factorization.

1216403587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195610 (or 195603 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 1216403587 is about 34876.9778937339. The cubic root of 1216403587 is about 1067.4787311000.

The spelling of 1216403587 in words is "one billion, two hundred sixteen million, four hundred three thousand, five hundred eighty-seven".