1216217212 has 24 divisors (see below), whose sum is σ = 2455173504. Its totient is φ = 516363312.

The previous prime is 1216217201. The next prime is 1216217239. The reversal of 1216217212 is 2127126121.

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 7 ways as a sum of consecutive naturals, for example, 199978 + ... + 205969.

It is an arithmetic number, because the mean of its divisors is an integer number (102298896).

Almost surely, 2^1216217212 is an apocalyptic number.

It is an amenable number.

1216217212 is an abundant number, since it is smaller than the sum of its proper divisors (1238956292).

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

1216217212 is a wasteful number, since it uses less digits than its factorization.

1216217212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406065 (or 406063 counting only the distinct ones).

The product of its digits is 672, while the sum is 25.

The square root of 1216217212 is about 34874.3058999029. The cubic root of 1216217212 is about 1067.4242093079.

The spelling of 1216217212 in words is "one billion, two hundred sixteen million, two hundred seventeen thousand, two hundred twelve".