1216564572 has 12 divisors (see below), whose sum is σ = 2838650696. Its totient is φ = 405521520.

The previous prime is 1216564571. The next prime is 1216564579. The reversal of 1216564572 is 2754656121.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 1216564572.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216564571) 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, 50690179 + ... + 50690202.

Almost surely, 2^1216564572 is an apocalyptic number.

1216564572 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1216564572 is an abundant number, since it is smaller than the sum of its proper divisors (1622086124).

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

1216564572 is a wasteful number, since it uses less digits than its factorization.

1216564572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101380388 (or 101380386 counting only the distinct ones).

The product of its digits is 100800, while the sum is 39.

The square root of 1216564572 is about 34879.2857151634. The cubic root of 1216564572 is about 1067.5258208666.

The spelling of 1216564572 in words is "one billion, two hundred sixteen million, five hundred sixty-four thousand, five hundred seventy-two".