1221043016 has 16 divisors (see below), whose sum is σ = 2289896700. Its totient is φ = 610403904.

The previous prime is 1221043013. The next prime is 1221043079. The reversal of 1221043016 is 6103401221.

It can be written as a sum of positive squares in 2 ways, for example, as 759222916 + 461820100 = 27554^2 + 21490^2 .

It is not an unprimeable number, because it can be changed into a prime (1221043013) 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, 42530 + ... + 65198.

Almost surely, 2^1221043016 is an apocalyptic number.

It is an amenable number.

1221043016 is a deficient number, since it is larger than the sum of its proper divisors (1068853684).

1221043016 is a wasteful number, since it uses less digits than its factorization.

1221043016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29408 (or 29404 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 1221043016 is about 34943.4259339293. The cubic root of 1221043016 is about 1068.8341498622.

Adding to 1221043016 its reverse (6103401221), we get a palindrome (7324444237).

The spelling of 1221043016 in words is "one billion, two hundred twenty-one million, forty-three thousand, sixteen".