1216515255 has 16 divisors (see below), whose sum is σ = 1951651680. Its totient is φ = 647065728.

The previous prime is 1216515247. The next prime is 1216515283. The reversal of 1216515255 is 5525156121.

It is not a de Polignac number, because 1216515255 - 2³ = 1216515247 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 103120 + ... + 114309.

It is an arithmetic number, because the mean of its divisors is an integer number (121978230).

Almost surely, 2^1216515255 is an apocalyptic number.

1216515255 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1216515255 is a deficient number, since it is larger than the sum of its proper divisors (735136425).

1216515255 is a wasteful number, since it uses less digits than its factorization.

1216515255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217810.

The product of its digits is 15000, while the sum is 33.

The square root of 1216515255 is about 34878.5787411127. The cubic root of 1216515255 is about 1067.5113955788.

The spelling of 1216515255 in words is "one billion, two hundred sixteen million, five hundred fifteen thousand, two hundred fifty-five".