1216555472 has 40 divisors (see below), whose sum is σ = 2574528672. Its totient is φ = 552297600.

The previous prime is 1216555453. The next prime is 1216555493. The reversal of 1216555472 is 2745556121.

It is a super-3 number, since 3×1216555472³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155822 + ... + 163442.

Almost surely, 2^1216555472 is an apocalyptic number.

It is an amenable number.

1216555472 is an abundant number, since it is smaller than the sum of its proper divisors (1357973200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1216555472 is a wasteful number, since it uses less digits than its factorization.

1216555472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8547 (or 8541 counting only the distinct ones).

The product of its digits is 84000, while the sum is 38.

The square root of 1216555472 is about 34879.1552650003. The cubic root of 1216555472 is about 1067.5231591339.

The spelling of 1216555472 in words is "one billion, two hundred sixteen million, five hundred fifty-five thousand, four hundred seventy-two".